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Messages - blackeagles
16
« on: July 30, 2022, 09:26:20 AM »
I'm hoping to try anything other than taking them off as the air box is built onto the rear mudguard and there is very limited space when you loosen the connector from it to the air chamber - maybe 5mm - which is supposed to be enough to 'wangle' the carbs off.
as I said earlier, it does run allbeit with odd settings so I'm firstly going to try taking the pilot screws out and spray carb cleaner into them and reset it all to a basic setting and see what happens
17
« on: July 27, 2022, 11:38:13 AM »
well, I'm not sure if its good or bad but I borrowed one of those cameras of a flexi connection and the acc. pump jets that point into the carb are clear as I can see a jet of petrol firing out of them into the carbs.
Its an odd thing but it was running well with the sync and pilot jet settings so far out originally - 1 and 4 were twice the reading of 2 and 3 AND the pilot screws had 1 and 2 set at 4 1/2 out and 3 and 4 set at 3 1/2 out so you would have thought it was running very rich at tickover but it was not!!
18
« on: July 25, 2022, 02:42:22 PM »
It is the pd50 carb and I had forgotten the acc. pump. I will have to drill out the screw in the clamps (rusted) and check.
19
« on: July 23, 2022, 10:07:54 AM »
I suspect I know the answer to this but I thought I would post my problem as there may be something I’m missing.
I have never had much luck with 4 cylinder carbs (3 too many) but I spotted a tatty 1981 cb650z so against my better judgement I thought “how hard could this one be?” so I have spent the last few months cleaning it up and now I have got to the carbs.
OK, the problem, it ran and ticked over well without any smoke/hunting or choking so I was going to leave it but being a meddler I had to check it and the carb sync showed 1 and 4 twice the value of the base carb and 3 just a little high but the real thing I could not live with was the slow running screws were set between 3 ½ and 4 ½ turns out ( the correct setting is, I think, 1 ½ out).
So anyway I re-synchronised them with the screws at still out and it ran hwhen hot so I reset the screws to 1 ½ and big surprise it no longer runs. It starts on full choke but if I touch the throttle it stops even when hot.
I’m going to guess they will have to come off but before I do that any other suggestions or things to check?
20
« on: December 06, 2020, 12:25:57 PM »
you could try checking (with a multimeter) the reading(s) to see how good/bad they are before anything else.
21
« on: September 20, 2020, 11:12:20 AM »
ok. given the 'apparent' good condition i am going to guess they were replaced some 12 years ago when the bike had a fair bit of renovation then stored until i got it.
i see ds sells the same ones but i will try new caps and cutting back the ht first to see what happens. i did buy a set of generic ones which only need the wires changing 'cos they have the wrong connectors but maybe i will get a set of ds ones if it continues.
plugs have only been run in the garage but for the cost a new set seems right.
22
« on: September 19, 2020, 11:52:17 AM »
thanks all and yes, i had not noticed the little 'k' at the bottom of the display so it is in 1000's.  it would seem that they are alright, well when they are cold at least. do coils break down when hot??? since there are no diodes/resisters etc in them to fall over just windings and an iron core!!!! i do not think these are the original as my old haynes says toyota denso and these are tek fl 703 so presumably they have been replaced at some time in the past. they look i very good condition and the ht cables are reasonably supple - they are thicker then the modern stuff - and no 'waggle' where they go into the coils. in fact the only thing to note was that the copper at the centre of the ht cable where the plug cap screws in was blackened on each one (quite shiny now as i've been pushing the probes in and out a lot) . i would rather keep the original coils if i can so i will be cutting the ht back say an inch and using the new caps when they arrive to see what happens. anything else i should check?
23
« on: September 18, 2020, 10:59:00 AM »
i'm not sure if the coils are 'wrong' or not but having finished the bike i took it for a 'shakedown' and in the last few miles it went onto 3. it started straight away on all 4 and has been ok running in the garage since so i am assuming it only happens when hot so intermittent and maybe a sod to find.
prim - slight fluctuation prob. the gauge
coil 1/4 - 4.5 to 4.6 ohms
coil 2/3 - 4.7 to 4.8 ohms
sec.
1/4 - 14.70 ohms
2/3 - 14.60 ohms
plug caps
1 - 5.68 ohms
2 - 4.29 ohms
3 - 4.81 ohms
4 - 5.48 ohms
i have bought new caps.
these readings seem ok to me but electrics is a 'dark art' as far as i'm concerned so not sure. obviously the readings are for a cold engine and since the 'running on 3' was when hot i'm not sure if it makes a difference or if it can be checked hot.
only other thing to say, and i still feel a bit dumb mentioning it, was that just before the problem there was a odd noise like a demented bird tweeting - only way i can describe it - which i was thinking may be a plug cap resister giving up.....maybe?.
any suggestions?
24
« on: September 14, 2020, 03:21:47 PM »
thanks for the info.
25
« on: September 12, 2020, 10:17:38 AM »
finally got round to sync'ing the carbs again with a carb tune.
i tried setting it at 3k rpm but its not what i would call reasonable at tick over so did it again at 1500 rpm and it's a little bit better but still not what i would like although i don't know what is reasonable for these bikes. still the revs die away even with the choke out initially but will tick over when slightly warm and it quite happy (revs do seem to raise and lower slightly) with no choke when warm but maybe this is normal!! set the warm tick over at 1200 rpm with very little chain rattle so i may have to live with it.
26
« on: July 20, 2020, 11:22:48 AM »
That #3 condition may be significant.
With the mixture screws, winding one out individually should give you a response from lean to rich if you go completely outside their range, say 1/2 turn out to 2 1/2 out, which is what you'd expect to see.
What you are looking for is one of them that doesn't have that linear response, indicating that the carb is not clear for that low speed metering. If one is impaired when tested like this then it won't matter what the clean ones do as they'll not overcome the irregularities from one poor performing carb.
That #3 would be the initial suspect.
The revs so unstable suggest that one cylinder is erratic in firing, which would give you that pulsing as it chimes in/ out.
when i alter all 4 screws in/out individually the revs change up and down so that seems to be working but i should explain that the fire via 3 is very intermittent and only happens when the setting is very rich but only on this carb! as far as the 'wavering' of the revs is concerned, i may be just expecting it to run ultra smooth since its 4 cylinders but i will (hopefully) know what is going on when the gauges arrive. i have connected a strobe light to each plug and the fireing looks even to me.
27
« on: July 19, 2020, 11:32:43 AM »
That is exactly what you change while synchronizing, but while you wait for the new set, why don't you put them all at the same height and see how it runs?
yes, i did that last thing, did it help?, well about just over 3/4 of a turn out so they all look level(ish) by eye and yes the tach went up by maybe 100rpm but it still has the very slight wavering effect. i know its an analogue tach so that may be the effect of the cable but the engine still sounds like its wavering (maybe that is standard). oh, slow running needle is 1 1/2 out. 1 1/4 revs drop maybe 100 rpm but hard to tell (tried the multi meter but the reading is up and down so much its unreadable), 1 3/4 out and revs increase maybe 100rpm, 2 out revs increase a little bit more but seems to be 'hunting' and beyond this they drop so 1 1/2 it is!! oh, oh, i see that no3 has a very occasional fire back into the carb - hope it goes away when i adjust them. soon find out!!
28
« on: July 18, 2020, 03:34:15 PM »
ok, thanks. well i am going to give it a little bit more thought before i give up and call for help
i have ordered a carbtune pro so i can, at the very least, check the setting the analogue ones are giving me.
this is going to sound a bit like i'm a simpleton but given that the factory used to churn out parts for carbs by the 1000's so they are likely to be almost identical...well i notice the adjustment screw/nut on the top of carb 1 has the screw head flush with the upper nut surface whereas 3 and 4 the screw is about 1/2 turn or so showing above the nut!! i'm grasping at straws but this surely can't be right??
29
« on: July 18, 2020, 10:45:39 AM »
no change if i pull in the clutch.
i'm supposed to be looking after my wife but i could not resist having a look. it was slightly sticking (slight bur due to the bolt being tightened with the shaft off centre) but a bit of emery and some copper slip made it slide nicely. the bolt marks on the shaft show it touches about half way so seems there is some adjustment left.
so rattle can only be the primary chain and i still think its due to uneven tickover (you can hear a slight change in the tickover and see the tacho needle moving slightly), so i'm still looking at the gauges not reading correctly - this is very similar to the poor initial running of the cb400f i did 2 years ago and it turned out to be the slow running jets being 'cleaned' and made oversize, a new set and it runs lovely!!
may have to beg, borrow or buy a decent set of gauges just to make sure the sync is ok before i yet again remove the carbs.
30
« on: July 17, 2020, 02:02:09 PM »
the more i look at it the more uncertain i get.
if i remove the 3 bolts holding the cam chain adjuster housing to the engine will it come away along with the tensioner push bar spring i.e as a complete unit? - i'm fairly certain mine is not moving as a while back i undid the adjustment bolt and nut and put a rod into the end and gave it a light tap and it sounded solid so left it.
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