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Messages - Scottish Badger
1
« on: May 08, 2023, 03:11:25 PM »
An update.
Leaking float needle seats confirmed on carbs 1 & 2. I drained both carbs, removed the fuel pipe from the tank (leaving the other two carbs full) and used airline to blow through carbs 1 & 2 in both directions! Reconnected fuel line, fuel tap on, no flooding. Great, I thought! Rode the bike, within 2 miles it was flooding again, this time on carb 2 only! Took it back home and virtually threw it into the workshop and went for a beer!
A few days later, I removed the carbs completely yet again.... I swear, these carbs should be able to remove themselves by now! After checking for any dirt in the in-line filter and carb float chambers (none), I set up a heath-robinson test rig with an air supply metered at 2psi and used leak detection fluid on the float valves to check for leaks, deliberately opening and closing them to try and provoke something.
I wasn't completely happy with any of them, so I trawled through all the carb kits I've bought (a cheap set from ebay, then another set from an allegedly reputable source after deciding the cheap ebay ones were crap quality!) and sat with some metal polish and a very small piece of tubing that just fitted onto the end of the needles and polished the needles to the seats. I've ended up using the UK-sourced brass with a set of original needles, I've also dropped the float heights by 1mm as well. Whilst it was up on the bike lift, I replaced the standard exhaust with a nice Delkevic system.
Yesterday, I took the bike out for a run and I'm relieved to say the carbs behaved perfectly, with no issues. However.... it seems I now need to replace the clutch, as despite adjustment being correct, it still slips slightly on hard acceleration going up through the gears. I also have a squeaking front brake, I suspect the caliper is binding very slightly, so that's another thing to add to the list......
On a positive note, I feel like I'm finally getting somewhere with it now, and the new Delkevic exhaust sounds just lovely under full throttle.
2
« on: April 03, 2023, 09:05:30 PM »
Hi Ted. Yeah, fuel usage at 30mph and above is enough to prevent the flooding.
Frustration prevented me from actually checking which carb it was, but I can assure you there was no dirt in there anywhere and the filter is still clean as well.
I'm thinking I'll find what carb it was, drain it down and blow it back with the airline after taking the filter off and see what (if anything) comes out the fuel pipe.
The interconnecting pipes were all like new, more of a plastic than a rubber but still quite maleable - and clean.
3
« on: April 03, 2023, 08:23:32 PM »
After resolving my previous cold start issues, today I finally rode my 400/4 for the first time seeing as it was a glorious sunny day on the Moray coast.
Now, I'm not a small chap (around 18st 6) so I never expected any spectacular performance, but it actually surprised me. Not with the speed or acceleration (never went over 60 and I was using a lot of throttle to maintain that speed into a light breeze), but how solid and planted it feels. It corners very nicely indeed, it's surefooted, stable and not upset by road surface changes etc. The highest praise I can give it, it's like a smaller, lighter version of my triumph Thunderbird Sport 900.
There's a minor adjustment required to the clutch, I think I may have taken just a little too much free play out at the adjustment under the engine cover as it wants to slip slightly when changing gear quickly and winding the power on. BUT........
Slowed to 20mph in a village, started running rough. Into 30 limit, open the throttle a touch and it clears itself. F8&%£"g carb flooding!! It's had new float needles and seats, float heights set (making sure the floats themselves are level), a filter in the line from the tank, clean fuel, and it's sat running on the bike lift for over two hours with no issues whatsoever. First time out, it floods one of the carbs! Stay over 30mph, it's fine. Slow down below 30 and it does it every time! Maybe it's trying to tell me something.......
4
« on: March 21, 2023, 06:55:44 PM »
Thanks Ted, that shows the fitment nicely. Clutch cable bracket is available from David Silver, that's where I got mine from. Cheers.
5
« on: March 21, 2023, 01:11:01 PM »
Hi Ted, yeah I was looking at those ones earlier. Do you know if the clutch cable guide is attached to one of the rocker cover breather cover bolts? Looks like I'm missing the cable "holder" that goes over the nearside tank mount spigot....
6
« on: March 21, 2023, 10:59:09 AM »
Hi folks, on to my next puzzle of "how the previous owner didn't put things together correctly...."
Can anyone help with photos of how the wiring harness is secured and properly routed on the nearside of the frame above the engine, and how the clutch cable is routed and any support brackets etc on the offside?
Thanks.
7
« on: March 21, 2023, 10:55:55 AM »
Gareth, the adaptors were in the right positions, but one was mounted 180 degrees out! Someone must have had one heck of a time and really persevered to force the complete carb set back in initially.......! I've found a few "bodges" as I've been working my way through the bike, at least I now know it's safe to go out on (when it warms up a bit, lol).
Just ventured back out to the workshop - fully cold, started first prod of the button with 3/4 choke. Happy days!
8
« on: March 20, 2023, 07:57:05 PM »
It's fixed!!!!
Hi folks. I finally got to the bottom of the bad starting. It was nothing to do with the ignition system, nor the carbs themselves.... but everything to do with the carb adaptor elbows on the head and the filter box connecting rubbers!
In frustration, I took the carbs back off and went through them meticulously - and found nothing untoward! I'd ordered up new mounts and rubber stubs in advance for the new engine (when I get round to building it!) but decided to fit them anyway. That was when I discovered that someone in the past has fitted the stubs the wrong way round and basically distorted them forcing the carbs into them - the combination of time and heat has kind of "set" them into that position, and most likely not sealing correctly. I also found silicon sealant on the o-rings between two of the adapters and the head, not good! The rubber connectors between airbox and carbs were hardened with age as well, and probably not sealing onto the carbs all that well - which I appreciate will cause midrange and possibly top-end fuelling issues, but shouldn't really have much effect on cold start.
My theory - the elbows onto the head weren't sealing properly and the cylinders were drawing air past them when cold, but they were sealing up after a little thermal expansion kicked-in, which is why I wasn't finding any leaks, I was checking with the engine hot!
After putting it all back together this afternoon, it started straight up within 2 seconds of pressing the starter button. Re-balanced the carbs again, engine purring like a kitten! The needle on no.1 gauge appears slightly different, that's how the camera "froze" them, the needles were constantly fluctuating a couple of degrees. [ Guests cannot view attachments ] [ Guests cannot view attachments ]
9
« on: March 08, 2023, 08:26:35 AM »
I've a funny feeling the 250RS uses the same cable as the XL250s, which is also common to the XL500s and some early FT500's as well. As said, CMS website will show interchangeability.
10
« on: March 08, 2023, 08:24:18 AM »
Welcome Gary, love the little 350. I'm not too far along the road from you, just the other side of Elgin. Currently working on my old 400/4 for the summer.
11
« on: March 04, 2023, 08:13:10 PM »
Cap, it's running from a separate fuel supply bottle at present, with fresh super-unleaded.
K2-K6, the coils are 4.8 Ohm so ought to be ok......
Not had a chance to do any further investigation this last week, the clutch went on one of my cars so that's been taking up my time. Turned into a nightmare of struggling to bleed the system, finding out I'd been supplied incorrect parts and now delays getting the right parts! Hopefully it'll be resolved early this coming week and I can get back to the bike!
12
« on: February 23, 2023, 07:13:05 PM »
K2-K6, that's an interesting point (no pun intended, haha). It never occurred to me to measure them, it was one of those "what the hell" moments..... I'll check next time I'm in the workshop.
However, I've done some digging back through old forum posts and found a bit of info on resistance - to be precise, the resistance of plugs and suppressor caps. Julie had said earlier to remove the Iridium plugs (which goes against the grain, to be honest as I've had such good results from them in the past) and fit a set of standard D8EA plugs, so I went back out to the workshop and found the original plugs I'd taken out and guess what - they're DR8EA! Cross-checking the suppressor cap part numbers, they are also 5Kohm items, so it seems there are two resistances, plug and cap, which won't have been helping. Your theory on the coil may be the reason it's giving a stronger spark now, if indeed it is? I've ordered a new set of D8EA plugs that should hopefully be here on my return, I'll fit those (and check primary resistance) and see if that helps matters.
I do have an electronic ignition setup that came with the bike (new in box, never fitted) so I'll look into that in more detail as well and see if it's compatible with these replacement coils.
13
« on: February 23, 2023, 05:21:53 PM »
This morning I did a cold compression test.
1. 135
2. 135
3. 135
4. 125
I'm not at all worried about these readings, I actually think they're reasonably acceptable for a 36,000 mile bike in a cold workshop in the north of Scotland, haha. I'm figuring no.4 is slightly lower because of that cylinder having previously been running rich due to the previously mentioned carb needle circlip being in the wrong groove when I bought it last October (Yes, I did say no.1, but I got it wrong, it was no.4, sorry.)
I then put the plugs back in and tried cranking with kill switch off, full choke, full throttle for a couple of seconds, then went for a start. Almost exactly the same as previous, the odd cylinder firing, but no start.
I then pulled the air filter and gave it a squirt of brake cleaner (not a lot, that stuff causes bad detonation!) and it was exactly the same.....!!!!
At this point I decided - because it was an option I hadn't tried - to replace the ignition coils with the spare new "di" marked ones I mentioned earlier and tried again. It fired up after about 4 or 5 seconds of cranking, roughly, coming onto all 4 within a few seconds more. Now, I had a big fat blue spark with the original coils, so I've no idea why this has made any difference.....
I'm off to Glasgow tomorrow then on to the Borders to pick up some XL500 engine parts, so I'll try it again from cold with the new coils fitted on Sunday or Monday and we'll see what happens. If the coils have cured it, I'll be quite happy, but I still don't understand why when the spark at the plugs was really good!
14
« on: February 23, 2023, 09:37:15 AM »
Hi Mike, it's being fed new, fresh super-unleaded shell fuel at present (which in the north of Scotland has no ethanol), from a separate fuel feed container.
15
« on: February 23, 2023, 08:27:21 AM »
Oddjob, caps are new, fitted as part of the full service.....
Gareth, levels were all checked when the carbs were apart, all seemed good.
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