Hi Folks, My restoration of the '71 lightning grinds on at glacial speed. I had the bottom end rebuilt by a renouned restorer and as far as I can tell it's a great job. However I had to take the Inner crankcase cover off because when I fitted the Kickstart lever it would jam every 4th or 5th kick.
I'm fairly confident I resolved this by replacing the kick pinion with one that didn't have flattened tops to the teeth.
While I was waiting for the parts to come I connected the oil pipes and filled the Oil tank (OIF) after 48hrs there was about a 2" puddle on the floor. On close inspection it appears to be coming from the seat of the oil pump. This pump I bought as new old stock and the restorer took it apart, cleaned it all up from the gunk of ages and put it back together.
I'm thinking that leaking oil from the pump cannot be a good thing even if it's not a huge amount. I plan to take the pump off and see if I can find a problem but I'm not going to take it apart. I know they are tricky. I will probably take it back to the restorer but before I do, do you guys agree that this doesn't sound right or might this be normal?
BTW I have checked it's not wet sumping by taking the sump off. Only a very little oil came out. I wondered if the sump had filled and was seeping past the main bearing but no. Actually just under the main bearing in the curved top of the pump a puddle has formed.
Thanks in advance, Glenn
It's possible the oil is seeping out from either the body of the pump, from its seat with the crankcase or past the non-return valve via the main bearing. If the NOS pump was fitted by the restorer, it is probably sensible for him to sort out any problem.
'Wet sumping', as you call it, would occur if the non-return valve in the seat of the pump allowed oil to drain back into the main bearing. If the bike was level and on its centre stand, this oil could mostly seep out of the right-hand side of the bearing, assuming its still got a bush fitted, as the thrust washer would hinder its flow out of the left-hand side.
I am sure it would be possible to check whether or not the oil is leaking from the main bearing, perhaps using a bit of talcum powder underneath. All engines of this sort, 'wet sump' to a greater or lesser extent and to put the problem into perspective it might be worth measuring how much oil leaks out over, say, 24 hours. I would have to check but, for example, 20 cc in 24 hours might be perfectly normal but even that would give a relatively big puddle on the ground.
Thanks for this Spaceman, great info and so quickly! Maybe I don't have a problem then. I will at the weekend set up a more scientific method of measuring the seepage. I assumed the only way it would come back was if the sump filled to the level of the bush but of course it makes sense the oil would come out via the bush in the first place. I don't fully understand what I would be looking for with the talcum powder. Would that be to put talc over bush and see if it comes through the bush via a circular oil mark? (yes nice new bush but will be fitting external filter).
Thanks again, much appreciated.
Cheers Glenn
Sometimes, it can be very hard to see the path oil has taken across engine surfaces when it has leaked out - in this case, it might be hard to tell if the oil has seeped out of the oil pump itself where it bolts on to the crankcase or has seeped out of the main bearing. This is particularly the case if the oil is new. The trick with talc is to dust the crankcase surfaces underneath the pump flange and just underneath the main bearing to try to make the oil path more visible.
Hopefully, the seepage is from the main bearing and not that much suggesting you don't have a have a problem.
Drain the oil tank and then refill with oil that has a dye in it. With a uv lamp you can track the oil flow pretty precisely.
you say it was jamming every 4 or 5 kicks, did you sort it?
its probably the end tooth on the kick start gear, normally grinding it lower on one or two teeth cures it.
Quote from: cdsdorset on 06 Dec, 2022, 08:08
Drain the oil tank and then refill with oil that has a dye in it. With a uv lamp you can track the oil flow pretty precisely.
Wow Hi tech! I like that.. Might see if I can hunt down a uv light.
Many thanks Glenn
Quote from: chaz on 06 Dec, 2022, 17:30
you say it was jamming every 4 or 5 kicks, did you sort it?
its probably the end tooth on the kick start gear, normally grinding it lower on one or two teeth cures it.
Well I have yet to properly test it but Initial tests seem to suggest yes. Certainly an improvement at least. The old sprocket though in good nick had really quite large flats on the top of the teeth but I replaced it with one which had nice pointed teeth. Seems to have done the job. I can take pictures if you're interested. On close observation the teeth of the kickstart quadrant would jam onto the flats of the sprocket. Hopefully the pointed teeth present much less opportunity for the quadrant to jam. Also the sprocket bush was a bit more worn than I would like so I replaced that to keep everything lined up as it should be.
I did try grinding down the first tooth a bit but that made no difference. I was about to start grinding further teeth when I noticed a nice pointed sprocket online so to avoid further butchery, I thought i'd try that first. £35 later....
Fingers crossed!
Cheers Glenn
:) :) :) :)
I have had your kick start problem a couple of times and its by no means rare. I found that when kicking the bike over if you dont let the kick start come right back to the top of its travel the teeth will stay aligned. If or when it jams, simly put it into gear and rock the bike. usually even the slightest rocking will release it.
Mike 8) 8) 8) 8)