Honda-SOHC
SOHC.co.uk Forums => CB350/400 => Topic started by: Nurse Julie on May 22, 2017, 07:02:58 PM
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Hi Chaps
Having problems with Hettie, the 400/4.
When first started from cold she idles fine at about 1100 rpm but when hot the idle increases intermittently to about 2000 rpm and then gradually settles back to 1100 rpm. Have had the carbs off today as I thought it may be dirty idle jets. Dismantled the carbs, blew everything out with airline, no blockages. Floats are where I set them last year, 21mm, re bench synced. Mixture screws at 2 turns. Couldn't find evidence of any air leaks on any rubber bits, refitted carbs.... still the same problem. Checked the timing / points all seem ok.
Where should I look next?
Ta in advance
Julie x
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I'm sure Trig will give the rubber parts a thorough inspection for you! Has the bike been laid up long? I more than a couple of months, always worth checking the advance weight pivot points on the timing unit, often overlooked and neglected of any sort of lubrication. The springs are not very strong when it comes to returning to static timing (idle speed), and sticky or rusty/dry pivot points can cause those symptoms.
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I have been riding her recently Hairy but to be honest she did do it sometimes last year as well. I will look at the bits you suggest and report back.
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My 400 does the same Julie!
Im always fumbling at the idle wheel on the carbs at the lights
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Haha, what, and burning your hand like I do when I have a fumble :o You have electronic ignition though Dave and pods fitted, so yours should run perfectly.
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Its a 40yr old bike,il forgive it for having a few ailments.
Yea its got electroinc ignition but the pods make it a nightmare to set up Juls
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Mine too. After 40 odd years there's probably wear and tear that makes them not 100% reliable.
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Yes Chaps, I hear what your saying, maybe I'm expecting too much from the old girl. It is a minor problem I know and she still rides very well, it's just a little niggle I would like to get rid of if possible.
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Just a thought... I had this once on another bike.
Is there enough free play in the throttle/cables ?
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I will check that also.
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Update. Cables definitely have enough free play and work just fine. Took the advance / retard unit apart, cleaned it up, put new washers and springs in and...........exactly the same problem. Never mind, I took her for a lovely fast ride around the Lincolnshire Wolds and other than this small problem, she is running so well, so I'm going to leave it at that for now.
Thanks for your suggestions.
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I have the same problem with my 400F.........
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Some further thoughts to consider;- usually you need about 2 degrees or more advance to get the engine revs to rise from just ignition so unless the a and r unit is obviously not dropping back as revs come down then it's unlikely.
Normally you're looking at an unmetered air supply of some source, this could be through the rubber intake seals as first consideration but it's not the only route.
The top of the carbs and the throttle spindles also have a route into the inlet that would not get fuel metered as required by going down the side of the slides.
You may be able to detect one carb leaking over the others by trying to trim the idle circuit one at a time, going richer or leaner should get a similar response in rpm change from each carb, if you get one with low or minimal effect as you change it then it could be that one requires more in depth inspection.
Also if you assume that high tickover shows its running lean in some way, do a test with all the idles a quarter turn richer to see if it gets a more consistent tickover.
Check also the engine crankcase breather, obviously it should be breathing! If it's badly restricted, then crankcase pressure builds and it can, if too high, pass air up past the pistons during the intake stroke ( with the carbs almost closed at tickover, it'll have quite a vacuum above the piston and positive pressure in the cases will try to go up past the rings) this is also unmetered and can make it run leaner than ideal.
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Thanks for your input K2-6 but the carbs have been stripped and rebuilt twice, the breather pipe is not restricted, as I have fumes in the airbox and she runs a little rich, rather than lean.As it is a high mileage, 46K, well used engine, the crankcase pressure is a little high as I get a little smoke from the breather tube. Have been out on her this evening and she's absolutely flying and a majority of the time, revs dropped back to 1100rpm. Its probably the intermittency of it that p••••s me off more than anything else.
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I know what you mean about tickover, it's just something that bugs us.
My brother in law ran a 400/4 years ago, commuted on it, went on holiday, etc etc it got to 107,000 mls before he replaced it! Even then it was mostly cycle parts that generally wore out, corroded etc. Cam chain was rattly though.
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Bloody hell, 107k on a CB400/4, I bet he had a sore arse ;D I think they are one of the most uncomfortable seats Honda ever produced. I suppose being a 70's sports bike Honda guessed all riders would have their bums out of the seat with knees and elbows scraping the tarmac ::) ::)
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If you only bench-synced the carbs, it's probably time to do an actual vacuum sync.
Weird idle definitely points to a poor synchronisation.
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I can get my carbs to within 1cm Hg but no better..... minimal knock after air screw adjustments.
Still think the rings and bores are bedding down after 1000 miles.
Max arse tolerance on the wooden 400f seat was an hour when I was young and supple !
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Max arse tolerance on the wooden 400f seat was an hour when I was young and supple !
Haha, you did well at an hour. I had my first 400/4 in the late 70's and found the seat awful even back then ;D
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If you only bench-synced the carbs, it's probably time to do an actual vacuum sync.
Weird idle definitely points to a poor synchronisation.
I vacuum sync my carbs every year and they still do this
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Well Dave, if you send me over the gauges you 'acquired' I will have a go. But in the meantime, it's such a fantastic evening, I'm off out for a ride and a rough bit of idle isn't going to stop me having fun.
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Have you checked the vacuum take off screws, as they only have a copper washer they can sometimes let by, i always put a twist of ptfe tape around these.
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I have got new aluminum sealing washers in place and I'm sure they are not leaking as only idles high when hot.
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It's an interesting problem, certainly with others saying the same in trying to get a constant idle.
Also the bit about running rich confuses me as anything I've worked with will usually hunt and drop rpm, eventually stalling if running rich at idle. Usually you'd have to give it more air to keep it going.
I always associate increasing idle with extra air assuming everything else is ok.
They use an air bleed on many fuel injected cars to control the idle with just a small amount of air bleed to raise even something like a V8 of 4lts, it's a surprisingly small amount. It's why many latter engines have o-rings on the dipstick, as when you pull it out it changes the idle as crankcase is vented into the intake systems.
S'pose it could be drawing some small amount of air down the inlet valve guides when hot if they've got a bit of wear of them.
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Air getting down the inlet valve guides sounds possible especially when hot.
Extra hot and slightly oily? air is also pulled in from the crankcase via the air box.
This must vary according to what volume is getting past the rings.
Might be worth checking the drain tube and the manifold vent tube underneath, the handbook says that one of these needs a squeeze periodically !
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I have got new aluminum sealing washers in place and I'm sure they are not leaking as only idles high when hot.
That's indicative of air leaks.
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I have got new aluminum sealing washers in place and I'm sure they are not leaking as only idles high when hot.
That's indicative of air leaks.
The bike does not have any air leaks.
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Think Kevski is referring to internal leaks ie blow-by gases ?
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Rising idle rpm says it does, it's whispering to you Julie ;)
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It must be the faintest of whispers then ;D ;D ;D. You are going to have to take my word on this, there really is no evidence of an air leak anywhere on that bike. I may be looking at this problem with only a basic knowledge of all things mechanical but, him indoors has also gone through everything possible and at this stage cannot find an obvious problem. And if Trigger can't find the problem (without stripping the engine) I stand no chance :'( :'( :'(
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I was trying to think of a way of testing any theory of valve guides or rings as a source without dismantling.
If while it's hot and idling too fast, then connecting a vacuum to the engine breather should possibly prevent internal transfer via the above bits. If the revs dropped during this it would indicate internal wear.
I don't disagree with you vis a vis external leaks not being present, but on any petrol engine I've worked on, uncontrolled idle is always too much air from some source.
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I know where your coming from and more diagnostics will take place. But, it only happens intermittently when hot. I was sitting in a fuel station tonight after a very fast and hard 40 mile ride, revs were idling at 1100rpm for at least 3 minutes, then all of a sudden, revs dropped and engine cut out. So, restarted the bike, rode another 6 miles, pulled up and the revs went up.Once the engine is very hot, I get exhaust gasses' into the airbox, indicating a small amount of pressure.
Edit...Its strange how other CB400/4 owners on the forum also have this problem and we can't all have the same air leak. ???
Edit, edit...for anyone that has read this post I originally put ' idling at 2200rpm' typo on my part. I have now changed the text to show the correct rpm at the time, which was 1100rpm.
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could even be spark plug threads blowing by or should i say drawing in, once hot and then resealing, then it could be one of many things, i am sure you will eventually find it.
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We love a good air leak on here :D
After your grilling you'll be able to withstand a full round of mastermind, specialised subject; unspecified air leaks within 1970s Honda 400 engine architecture. ;D
Thinking about it, I was trying to flip the problem to see where I got. Sooooooooo, if you had the throttle tickover adjustment set so it gave a high idle when hot ( as in it was properly being held there) then consider it's too rich on idle screw adjustment to give stable idle over a full heat range.
To test that, you'd have to lean the idle jets off by half a turn which should speed up the tickover, then drop the tickover master screw back out to bring rpm back in range. Maybe this would give a more linear setup over a wider heat range.
Then get it hot again to see what you've got.
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We love a good air leak on here :D
After your grilling you'll be able to withstand a full round of mastermind, specialised subject; unspecified air leaks within 1970s Honda 400 engine architecture. ;D
Thinking about it, I was trying to flip the problem to see where I got. Sooooooooo, if you had the throttle tickover adjustment set so it gave a high idle when hot ( as in it was properly being held there) then consider it's too rich on idle screw adjustment to give stable idle over a full heat range.
To test that, you'd have to lean the idle jets off by half a turn which should speed up the tickover, then drop the tickover master screw back out to bring rpm back in range. Maybe this would give a more linear setup over a wider heat range.
Then get it hot again to see what you've got.
Well, they say great minds think alike, we did try that the other day and it made no difference at all :'( :'(
I think I'm going to have to start right at the beginning again with the diagnostics and just keep plugging away until I find the problem. I took her out this morning and she was running like a bag of shite at low revs and running very hot. Gave up on her this evening and we took a pair of Honda CD250U's for a blat around the Wolds, great fun.
As for Mastermind, I won't sign up for it until this problem is sorted ;D ;D ;D
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It'll be interesting if you find what's giving the problems. As you say we've thought along the same lines.
Have you checked the resistance of the plug caps to see if they're ok, also you could try it on a higher octane fuel if it's on std.
My mastermind specialisation would probably be something like VAG group passenger car diesel engine oil specifications from the period 2000 to 2008 ;D
Yeh, I know I need to get out more but my household to-do list is so long that I need a bike to get from one end to the other of it :(
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One of my bikes had an idle problem. Part of the problem (but not the only one) was using resister plug caps and resister plugs. This doubles the resistance and caused part of my problem. Silvers website specify the resister plugs so the problem may be widespread. Sorry to say, the other part of the problem was an air leak at the isolator rubbers, and it caused an identical problem to yours......... On a side note I have always used NGK plugs until recently. A friend of mine said to try Denso plugs, and they make a significant difference to the running and idling on all my old bikes. I am told Honda specify Denso plugs as standard, but not sure that is true.
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Thanks both Roy and K2-K6, your thoughts give me more things to try.
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I tracked down air leaks on my old Brit stuff using 'easy start' - any leaks of unmetered air on the inlet side show up with a corresponding increase in revs. I also used it to good effect very recently on the supercharger elbow seals on my Daimler when all else had failed to find the rough running - there is a heck of a lot of potentially troublesome pipes in that there engine bay!
I also found a flattened o ring on one intake rubber (carb to head) on the 350/4 a few years ago.
I have never tried it on inlet valves on these fours and apart from getting splashed with hot oil, might work with a tappet cap off and a squirt of easy start aimed at the spring area.
Be careful though - it's very volatile and an old farmer friend used to say 'don't use it too often, them engines can get to depend on it!'
Not sure of any long term damage to rubber components - perhaps Ash might know better?
Ian
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Thanks Ian
I will add that to the list of things to try.
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I saw someone starting an old engine the other day and instead of using eazistart, which they didn't have, they used Lynx! Yep the boys perfume.
I suppose for air leak testing on these old bikes you could use Brut for that proper 70's vibe. It's only a pound a tin in Savers chemists, so cost effective too. ;D
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Honda might respond better to Hai Karate ;D
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Think you may have something there Clem.
Perhaps Brut should be used for old Suzuki two strokes and BMW boxer twins given their promotion by both Barry Sheene and Henry Cooper.
Maybe a little Chanel No 5 for an old Motobecane?
;D
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Plenty of ideas there chaps but no way am using my Chanel No.5 for diagnostic purposes!!!. No diagnostics going out at the moment as away in Prague with 4 girlfriends, all Nurses, so will fettle more next week.
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Plenty of ideas there chaps but no way am using my Chanel No.5 for diagnostic purposes!!!. No diagnostics going out at the moment as away in Prague with 4 girlfriends, all Nurses, so will fettle more next week.
you have a good "fettle" in Prague with the nurses!!
then you can come back and work on the CB !!
Have fun !!
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It reads that your bike is running weak for some reason- I guess the plugs are a good colour. Most of the things you can check won't need to throw money at it, which can be annoying as well as costly.
i had a lack of power problem which turned out to be the ruddy seat blocking the air-intake. took ages to find as it was so intermittent.
My petcock was in a poor state- but allowing fuel flow into a can didn't reveal it- I've tried to attach a photo of the state of it- [attachimg=1]
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That clogged up fuel filter may be indicative of rust in the tank. Been there, had a superdream tank hammered to fit for a while until I found a replacement. Not a pretty sight.
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Mike- The bike was awarded a better tank due to internal corrosion and the fact i got one that had a better paint-job. However, the tank its running on had a poor attempt some years back by the look of it- bits flaking off. So, I fitted an inline filter and so far, so good- and that was about 3 years ago (I've owned the bike since 2009).
To the original post- Ive got a spare set of carbs that i brought off ebay for about £70 one winter, as I thought my bad running was carb related- even though Id replaced a full jet-kit to ll carbs (turns out it wasn't, but its good to have spares for these 40-year old machines if you can come by them!) To my spare set, I also fitted a jet-kit...just in case. From memory, as they were not on the bike more than a couple of hours- they ran like you described- poor idling and that was after complete cleaning using the old fashioned method of carb cleaner and air-gun.
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What does it run like after you clean the filter? My was so clogged with rust particles it run rough and was a pig to start.
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Bike runs fine now , but back to the original query for help.
My rebuild was only successful after curing previous problems
1. The battery must be working correctly in terms of static 12v measurement and charging
2. The fuel supply/carbs must be working correctly- preferably with new jets and seals- the prime offender is the main-jet seal, which if defective will cause incorrect mixture because fuel runs down the side of the jet, rather than being metered correctly
3. Air supply- i ignored this to my peril!
We are all different- i prefer mine to run properly, start etc and am less concerned about it looking pretty. I therefore concentrate my efforts on what i can!
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A little update on this idle problem.
The 400 is a old engine that burns a little oil and does pump out some vapour from the breather in to the air box. checked everything for any leaks and no leaks found. Set the air screw out at 2 1/2 turns. Changed the plugs from DR8ES-L's to D8EA's and after a 12 mile test run, the idle is sitting OK. Engine temp has dropped but, also the air temp has dropped so, engine running cooler and ticking over fine.
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Was you running with ngk plug caps as well, because two lots of resistors gives problems, not wanting to teach you how to suck eggs but it's a common mistake and I have made that one myself.
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Was you running with ngk plug caps as well, because two lots of resistors gives problems, not wanting to teach you how to suck eggs but it's a common mistake and I have made that one myself.
Ermmmm, Yes, that was my doing :-[ :-[ :-[ I serviced the bike last and the time before I think and I had some DR8ES's laying around that I purchased from DS a couple of years ago. Now, my logic tells me that I would have put in the same as I had taken out. Taking in to account the bike has had this problem since I got her, maybe this is why. Strange though as DS still show the DR8's as suitable for the 400/4. I still think the worn engine has something to do with it but will see how she gets on.
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Was you running with ngk plug caps as well, because two lots of resistors gives problems, not wanting to teach you how to suck eggs but it's a common mistake and I have made that one myself.
Ermmmm, Yes, that was my doing :-[ :-[ :-[ I serviced the bike last and the time before I think and I had some DR8ES's laying around that I purchased from DS a couple of years ago. Now, my logic tells me that I would have put in the same as I had taken out. Taking in to account the bike has had this problem since I got her, maybe this is why. Strange though as DS still show the DR8's as suitable for the 400/4. I still think the worn engine has something to do with it but will see how she gets on.
I still think the worn engine has something to do with it
Get him indoors to sort it while he is doing mine ;) ;)
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Was you running with ngk plug caps as well, because two lots of resistors gives problems, not wanting to teach you how to suck eggs but it's a common mistake and I have made that one myself.
Ermmmm, Yes, that was my doing :-[ :-[ :-[ I serviced the bike last and the time before I think and I had some DR8ES's laying around that I purchased from DS a couple of years ago. Now, my logic tells me that I would have put in the same as I had taken out. Taking in to account the bike has had this problem since I got her, maybe this is why. Strange though as DS still show the DR8's as suitable for the 400/4. I still think the worn engine has something to do with it but will see how she gets on.
I still think the worn engine has something to do with it
Get him indoors to sort it while he is doing mine ;) ;)
Ha, I am at the end of a very long queue Paul, I keep getting knocked back by customers joining the list.....not pointing fingers obviously 😊😊😊
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Was you running with ngk plug caps as well, because two lots of resistors gives problems, not wanting to teach you how to suck eggs but it's a common mistake and I have made that one myself.
Ermmmm, Yes, that was my doing :-[ :-[ :-[ I serviced the bike last and the time before I think and I had some DR8ES's laying around that I purchased from DS a couple of years ago. Now, my logic tells me that I would have put in the same as I had taken out. Taking in to account the bike has had this problem since I got her, maybe this is why. Strange though as DS still show the DR8's as suitable for the 400/4. I still think the worn engine has something to do with it but will see how she gets on.
I still think the worn engine has something to do with it
Get him indoors to sort it while he is doing mine ;) ;)
Ha, I am at the end of a very long queue Paul, I keep getting knocked back by customers joining the list.....not pointing fingers obviously 😊😊😊
What me ;D can't be Im off to Sunny Cyprus 8) 8)
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Resume:
Fit D8EA Plugs and "plugs caps without resistor"?
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Was you running with ngk plug caps as well, because two lots of resistors gives problems, not wanting to teach you how to suck eggs but it's a common mistake and I have made that one myself.
Ermmmm, Yes, that was my doing :-[ :-[ :-[ I serviced the bike last and the time before I think and I had some DR8ES's laying around that I purchased from DS a couple of years ago. Now, my logic tells me that I would have put in the same as I had taken out. Taking in to account the bike has had this problem since I got her, maybe this is why. Strange though as DS still show the DR8's as suitable for the 400/4. I still think the worn engine has something to do with it but will see how she gets on.
I still think the worn engine has something to do with it
Get him indoors to sort it while he is doing mine ;) ;)
Ha, I am at the end of a very long queue Paul, I keep getting knocked back by customers joining the list.....not pointing fingers obviously 😊😊😊
What me ;D can't be Im off to Sunny Cyprus 8) 8)
Yes, I have heard your stalking me to Cyprus.........it won't get your engine done any quicker ;D ;D ;D
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I'm going first so it must be the other way around !
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Was you running with ngk plug caps as well, because two lots of resistors gives problems, not wanting to teach you how to suck eggs but it's a common mistake and I have made that one myself.
Ermmmm, Yes, that was my doing :-[ :-[ :-[ I serviced the bike last and the time before I think and I had some DR8ES's laying around that I purchased from DS a couple of years ago. Now, my logic tells me that I would have put in the same as I had taken out. Taking in to account the bike has had this problem since I got her, maybe this is why. Strange though as DS still show the DR8's as suitable for the 400/4. I still think the worn engine has something to do with it but will see how she gets on.
I still think the worn engine has something to do with it
Get him indoors to sort it while he is doing mine ;) ;)
Ha, I am at the end of a very long queue Paul, I keep getting knocked back by customers joining the list.....not pointing fingers obviously 😊😊😊
What me ;D can't be Im off to Sunny Cyprus 8) 8)
Yes, I have heard your stalking me to Cyprus.........it won't get your engine done any quicker ;D ;D ;D
Or leave the caps and fit these Denso X27ES-U
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They sound expensive Paul, I will have to start saving my pennies ;D
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They sound expensive Paul, I will have to start saving my pennies ;D
£8.10 for 4 delivered
http://www.ebay.co.uk/itm/121877231832?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT
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They sound expensive Paul, I will have to start saving my pennies ;D
£8.10 for 4 delivered
http://www.ebay.co.uk/itm/121877231832?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT
Yes, like I say, too bloody dear 😊😊
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And there was me, thinking you loved and cherished your bike - even giving it a name. Ha.
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And there was me, thinking you loved and cherished your bike - even giving it a name. Ha.
All my bikes have names Mike, many not suitable for a public forum and others I can't even remember :'( I have given it some thought and will order some but not until I can find them at a price as low as I now pay for NGK's.........and that is very low ;).
Ps...there was also a Dakota at Coningsby today.
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And there was me, thinking you loved and cherished your bike - even giving it a name. Ha.
All my bikes have names Mike, many not suitable for a public forum and others I can't even remember :'( I have given it some thought and will order some but not until I can find them at a price as low as I now pay for NGK's.........and that is very low ;).
Ps...there was also a Dakota at Coningsby today.
I have just fitted 4 D7EA's and they were £5.99 for 4 ,with free P&P
but I guess Trig buys them wholesale at 99p a bucket full
they us the Dakota as a training aircraft for the Lanc,a large tailwheel configuration makes them similar to fly
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All my bikes have names too...
Normally
"Feckin fireblade"
"Feckin bultaco"
"Feckin ______" (insert anything I own)
There's a Patten
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Yes Jason, it sounds oh so familiar ;D
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Been on a Dakota - out of Staverton airfield.
My brother said it was his first time in an aeroplane.
I said it was my first time I've ever landed in an aeroplane.
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Was you running with ngk plug caps as well, because two lots of resistors gives problems, not wanting to teach you how to suck eggs but it's a common mistake and I have made that one myself.
Ermmmm, Yes, that was my doing :-[ :-[ :-[ I serviced the bike last and the time before I think and I had some DR8ES's laying around that I purchased from DS a couple of years ago. Now, my logic tells me that I would have put in the same as I had taken out. Taking in to account the bike has had this problem since I got her, maybe this is why. Strange though as DS still show the DR8's as suitable for the 400/4. I still think the worn engine has something to do with it but will see how she gets on.
Keep up guys, am pretty sure I mentioned this on page 3 and on other threads. Its all Silvers fault for listing the wrong plugs. ::) These are the Denso plugs I use, cheapest around. http://www.gsparkplug.com/1x-denso-standard-spark-plugs-x27es-u-x27esu-067800-4140-0678004140-4114.html?___SID=U
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Was you running with ngk plug caps as well, because two lots of resistors gives problems, not wanting to teach you how to suck eggs but it's a common mistake and I have made that one myself.
Ermmmm, Yes, that was my doing :-[ :-[ :-[ I serviced the bike last and the time before I think and I had some DR8ES's laying around that I purchased from DS a couple of years ago. Now, my logic tells me that I would have put in the same as I had taken out. Taking in to account the bike has had this problem since I got her, maybe this is why. Strange though as DS still show the DR8's as suitable for the 400/4. I still think the worn engine has something to do with it but will see how she gets on.
Keep up guys, am pretty sure I mentioned this on page 3 and on other threads. Its all Silvers fault for listing the wrong plugs. ::) These are the Denso plugs I use, cheapest around. http://www.gsparkplug.com/1x-denso-standard-spark-plugs-x27es-u-x27esu-067800-4140-0678004140-4114.html?___SID=U
You most certainly did Roy and as usual I took no bloody notice of what any Man says ;D ;D ;D
Him indoors was under the impression that I was using the non resisted plugs anyway but I wasn't. I have only been out on her once since Trig fitted the other plugs as have been riding other bikes but I'm hopeful it may have cured the problem but, as Trig said before, the engine does need some internal work done as she has oil vapour in the airbox. It can wait until winter though.
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Try the Denso plugs Julie, they made a huge difference on my 750. And pretty cheap from the Green Spark Plug Company, you never know.
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I will give them a go Roy.
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Put a set of NGK 8EV in and the bikes idling nice now.
No fluctuating Julie.
Give Trigger a slap on the back for me
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Good Dave, that's you all sorted then.
I will give Trig a slap ;) ;) ;)
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Very interesting all this.
I'm having the same problem. Bike won't idle once engine is hot. Warm, it runs beautifully, but HOT.. the idle keeps slowing down and dying. I've tried airscrew settings 2,5 / 2 / 1,75 / 2,25. It's makes a small difference, but it will definately not idle for long.
Plug 'reads' rich with a carbon matt-black color.
If I understand correctly, either the plugs, or the caps should have resistance, right? So not both, and not neither.
I have recently replaced plugs (DR8ES?), caps (VD05F + XD05F), coils and points. Got 4 new NGK plugs on the shelve.
How do I recognize if my caps are with or without resistance, and how to recognize if the plug are with or without resistance (does the R in the type name give it away)?
thanks
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yes ,the "R" stands for resister,
if you have a multi meter,you can check the plug caps,
check your advance,and timing,the plugs should be cleanish after a run and tickover ,try to lean the tickover even more
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My multimeter has died a while ago and still needs replacing ::)
The ngk plug caps read 5 kOhm on them.
So i just tried the denso plugs, and the ngk d8ea. Why so fast after oneanother you wonder?
Well, after running idle a while (warming up has always been fine), the engine now starts running on 2 (?) cylinders and dies. Restarting gives a rough 2 cilinder rumble.
On further research, the coils (new ones from wemoto) feel totally different in temperature. One is just warm, the other hot, almost painful to touch...
I have to say, the 2 wemoto coils are a slightly different version between eachother. Think something is up there?
What's this about? ???
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you could swap plug leads 1-4 with 2-3,and alter contact breaker cables,see if the trouble migrates,
I had similar issues with a DSS supplied coils,one failed after less than a year
if you can borrow a meter check the coil windings when warm
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So, tried again today and bike started on 2 cylinders right away. No warm up required. Unplugged caps 1 and 4 and found that the new wemoto coil which was installed on the right side didn't function anymore.
I put the original coil back and bike runs fine on all 4 again.
Strange of the wemoto product.. hope they are reasonable with guarantee. Obviously i altered the coil to fit and trimmed the leads...
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Update on the idle problem on Hettie the CB400/4.
After changing the DR8ES's for the D8EA's the fluctuating idle problem was resolved. Anyone reading this that sees the DR8ES's that David Silver sells for the 400, it is a wrong listing IF you have resisted plug caps fitted, which most of us do.
Now, on to the next problem. Last year, only on one occasion I had a rattle from the engine somewhere. It only lasted a couple of miles and then went away. I didn't think too much about it to be honest. Riding this season the rattle has returned on several occasions, most probably from the top end, possibly on the left somewhere, and there has been a slight loss of power associated with the rattle. What with the oil misting in the airbox, probably due to increased crank case pressure and now this noise, I have taken Hettie off the road.
The plan will be a complete engine strip, assessment and rebuild over the winter. I really want to do this myself if I can, with lots of advice from him indoors obviously. I will start a new thread for this.
In the meantime, luckily, I have plenty of other bikes to ride so will still be out and about enjoying what is left of the summer.
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Can't you put a web cam up in the workshop. Might get better ratings than the Osbourne's ;D ;D ;)
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Can't you put a web cam up in the workshop. Might get better ratings than the Osbourne's ;D ;D ;)
Haha, now that would be a laugh. According to Graham I can't even hold a spanner correctly and it does get somewhat fractious when we're working together.....so it would definitely be akin to the Osbourns in full swing ;D ;D
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Haha, now that would be a laugh. According to Graham I can't even hold a spanner correctly and it does get somewhat fractious when we're working together.....so it would definitely be akin to the Osbourns in full swing ;D ;D
Wait, there's a correct way to hold a spanner? I bet I'm doing it wrong :-[
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Haha, now that would be a laugh. According to Graham I can't even hold a spanner correctly and it does get somewhat fractious when we're working together.....so it would definitely be akin to the Osbourns in full swing ;D ;D
Wait, there's a correct way to hold a spanner? I bet I'm doing it wrong :-[
I have been told I also don't know how to use a screw driver or ratchet and sockets correctly and as for using a Vernier correctly.....forget it. I am OK with a hammer but usually use the 'wrong' hammer ::) ::)
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My Missus is a wonderful person....and I do love her to bits.....honest. But she has a completely different way of doing things than I do. If I wallpaper and paint a room, I'll clear EVERYTHING out first and cover the carpets with substantial dust sheets etc (get the picture), removing or masking stuff up which might get covered in paint or paste, but she will just shift the furniture around as she goes. DOH. If she grouts tiles, she will wear her distance glasses (instead of her reading glasses - i.e. for close up work) and the grout is just a bloody mess with great gobs of it in the gaps. DOH. She always comes up with the solution to any problem I'm having with the daftest possible answer and the one that - although I have given it some thought, I have also discarded it early in the process..........always earning (well getting - at any rate) my peculiar brand of evil sarcasm which I have finely honed over my 67 years - and is not to be taken lightly. Luckily she doesn't hold grudges and we always get on fine after the dust has settled.
I have tried over the years to 'train' her - as I was trained during my Apprenticeship, but it's really no use, as she is just wired differently. Her Sister is just the same and she always breaks stuff trying to install or build it - usually because she either doesn't have the right tools or doesn't know how to use the right tool. She is always complimentary when I fit something for her.....but I always say that it's easier for me because I was trained how to do it and shown how to do it by good Tradesmen.
I don't know what the answer is (I'd be a millionaire if I did) but I have found that if she stays out of my way when I'm working....and doesn't offer her brand of barmy advice, we can get along fine and the jobs she wants doing eventually get done. She asked me yesterday 'When am I going to stop buying bike parts' ........having just received yet another old Triumph Engine in a bloody big crate ! I just smiled and she said nothing, so maybe she's getting the message after 25 years.
Having said all that, she's dead funny, a bloody great cook and a great judge of character and I love her to bits.........and I wouldn't swap her for all the tea in China.
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Ahhh, that's really sweet. Yes, I am learning that saying nothing and staying out of the way is usually the best policy. As for getting in a mess, you ought to see the mess I make when I'm plastering a room !!! :-[ :-[ :-[ :-[