I see it frequently, hence why I suggested it was the problem way back in this thread, the early K series also had clutch splines wear out frequently, as do the 1100 and 1150 models ..
Audio Diagnostic Please. It doesn't sound right and has no drive...
- Thread starter Lawrence_NZ
- Start date
Its just a big meccano set for big boys, patience is key, none of it is beyond the average home mechanic.
It all comes apart and goes back together easily enough, the only drama I found was getting the rear subframe to align with its bolt holes whilst trying to engage the driveshaft splines onto the gearbox at the same time, you need many hands. An option would be to fit the subframe to the engine/gearbox without the swinging arm fitted, then rebuild things in stages but I just put half the bike back together in one go to save time.
I think last time I did a Hexhead clutch, I used a ratchet strap to keep the back half of the bike roughly in place under slight tension whilst I jiggled the driveshaft around to get it horizontal and engaged on the gearbox splines, then ratcheted it forwards and got the frame mounting bolts in.
Hopefully the legend that is Steptoe will be along soon with a few hot tips for reassembly, I've only done three hexhead clutches, he must have done dozens.
As for lubricating the splines, a lot of old timers would periodically strip their boxers apart to lube the gearbox/clutch splines as preventative maintenance. I would recommend burnishing the splines with a little Moly 60 paste to provide a small degree of appropriate lubrication, but go easy and wipe off any excess........ Do a bit of googling on how Molybdenum Disulphide bonds alternating layers of Moly and sulphur to sliding surfaces like shafts, splines etc for lubrication and remains working even when dry.
It all comes apart and goes back together easily enough, the only drama I found was getting the rear subframe to align with its bolt holes whilst trying to engage the driveshaft splines onto the gearbox at the same time, you need many hands. An option would be to fit the subframe to the engine/gearbox without the swinging arm fitted, then rebuild things in stages but I just put half the bike back together in one go to save time.
I think last time I did a Hexhead clutch, I used a ratchet strap to keep the back half of the bike roughly in place under slight tension whilst I jiggled the driveshaft around to get it horizontal and engaged on the gearbox splines, then ratcheted it forwards and got the frame mounting bolts in.
Hopefully the legend that is Steptoe will be along soon with a few hot tips for reassembly, I've only done three hexhead clutches, he must have done dozens.
As for lubricating the splines, a lot of old timers would periodically strip their boxers apart to lube the gearbox/clutch splines as preventative maintenance. I would recommend burnishing the splines with a little Moly 60 paste to provide a small degree of appropriate lubrication, but go easy and wipe off any excess........ Do a bit of googling on how Molybdenum Disulphide bonds alternating layers of Moly and sulphur to sliding surfaces like shafts, splines etc for lubrication and remains working even when dry.
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Lawrence_NZ
Registered user
ratchet will be my first method and see how that goes.
I have an oil leak it appears from the bolt at the base of the clutch. I have not noticed any oil drops prior or even while it was parked up. The inside of the gearbox also looks dirty but not soaked in oil. I realise the bike is on an incline but as the leak appears to be the bottom of or at least lower portion of the engine this might be due to the dissasembly? Engine oil has not been drained prior to dissassembly.
I have an oil leak it appears from the bolt at the base of the clutch. I have not noticed any oil drops prior or even while it was parked up. The inside of the gearbox also looks dirty but not soaked in oil. I realise the bike is on an incline but as the leak appears to be the bottom of or at least lower portion of the engine this might be due to the dissasembly? Engine oil has not been drained prior to dissassembly.
That looks like engine oil to me rather than gear oil.
Check the seal around the balance weight shaft at the bottom of the engine casing inside the clutch housing. You can unbolt the balance weight, it is simply keyed onto its shaft in the correct orientation.
Also check the crankshaft rear main oil seal with the clutch removed.
No idea if the bolt has a sealing washer underneath the head, or even what the bolt is for without consulting a parts fiche. Hopefully an easy fix with a bit of research, if all else fails perhaps remove and clean the bolt and use some PTFE plumbers tape on the threads and bolt head then refit it to seal the leak?
Also check the gearbox input shaft seal, the early 1200's (including my own) had issues with this seal leaking.
Check the seal around the balance weight shaft at the bottom of the engine casing inside the clutch housing. You can unbolt the balance weight, it is simply keyed onto its shaft in the correct orientation.
Also check the crankshaft rear main oil seal with the clutch removed.
No idea if the bolt has a sealing washer underneath the head, or even what the bolt is for without consulting a parts fiche. Hopefully an easy fix with a bit of research, if all else fails perhaps remove and clean the bolt and use some PTFE plumbers tape on the threads and bolt head then refit it to seal the leak?
Also check the gearbox input shaft seal, the early 1200's (including my own) had issues with this seal leaking.
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I remove the shaft, fit the subframe. Then drop down the final drive and refit the drive shaft. 5 minutes of work refitting the driveshaft saves a hell of a lot of fucking around trying to fit the subframe with the drive shaft in place. Bare in mind I’m doing the job on my own with no help.
video on youtube of a bod in Thailand (or somewhere) doing a clutch - he does ALL THREE SEALS at the same time 2 on the box and the Rear main
might be this one
I can't find that bolt on any of the parts fiche, sorry. It might mentioned somewhere be in the REPROM I sent which could explain its purpose and whether it is safe to remove it or not.
Steptoe's suggested method to first remove the driveshaft, replace the FD/Wheel and then attach the subframe makes great sense. That way once it is bolted on you can easily remove the wheel again, swing down the FD at its knuckle and then insert/fit the driveshaft.
That front driveshaft to gearbox spline is still a pain in the arse to get engaged, but at least you aren't fighting against the whole bike.
Steptoe's suggested method to first remove the driveshaft, replace the FD/Wheel and then attach the subframe makes great sense. That way once it is bolted on you can easily remove the wheel again, swing down the FD at its knuckle and then insert/fit the driveshaft.
That front driveshaft to gearbox spline is still a pain in the arse to get engaged, but at least you aren't fighting against the whole bike.
A leaking engine balance shaft seal is far more common than an engine rear crank main seal.
Lawrence_NZ
Registered user
Lots of time under the bridge and lots of help and encouragement from @Pukmeister has got me pretty close:
I've also sent questions to @Steptoe for guidance which has been great.
Progress to date:
- Bike came apart relatively easily. Videoing the wiring was helpful but not as helpful as putting painted marks on each of the connections would have been. I did not do this and regret it so if anyone is facing the same job, use a marking scheme...
- Clutch parts that @Pukmeister sent through arrived and fitted well. Many thanks!
- All splines lubed up with the care pack included in the clutch parts.
- New gaiters on each end of the driveshaft.
- New seals in and around the gearbox fitted.
- Bike reassembled with a brief hiatus for helicoil repair on one for the lower large bolts. It had stripped on the way out and I feel pretty good about the fix in terms of strength with the coil.
- Wiring reassembled with the exception of one wire that appears capable of connecting to three different sockets. It might not be in use but looks clean enough on the connector that gives me pause for thought.
- Final drive and gearbox oil changed.
Current status:
All assembled other than some fairing pieces, fueled up and it starts sometimes.
When it starts on the stand, I am able to shift it through the gears so that makes me think the clutch job is done. Hooray!
1. The downside it I am currently getting what sounds like the starter motor not engaging every time. It whirs well and vigorously like it is spinning freely. Restarting/resetting the ignition key off and on again allows the engine to turn over. So this is an intermittent issue.
2. I thought I'd do the engine oil swap while it is out of action and having other fluids changed. Letting it idle allows it to run for about a minute before it either chokes itself out or runs so lean it cuts out. I suspect I have moved the throttle cables out of whack. I'm doing some more experiments to see if I can get something more definitive to aid in identifying this issue. I have a few litres of fuel in there but might increase this to rule it out as lower than it would like.
I've also sent questions to @Steptoe for guidance which has been great.
Progress to date:
- Bike came apart relatively easily. Videoing the wiring was helpful but not as helpful as putting painted marks on each of the connections would have been. I did not do this and regret it so if anyone is facing the same job, use a marking scheme...
- Clutch parts that @Pukmeister sent through arrived and fitted well. Many thanks!
- All splines lubed up with the care pack included in the clutch parts.
- New gaiters on each end of the driveshaft.
- New seals in and around the gearbox fitted.
- Bike reassembled with a brief hiatus for helicoil repair on one for the lower large bolts. It had stripped on the way out and I feel pretty good about the fix in terms of strength with the coil.
- Wiring reassembled with the exception of one wire that appears capable of connecting to three different sockets. It might not be in use but looks clean enough on the connector that gives me pause for thought.
- Final drive and gearbox oil changed.
Current status:
All assembled other than some fairing pieces, fueled up and it starts sometimes.
When it starts on the stand, I am able to shift it through the gears so that makes me think the clutch job is done. Hooray!
1. The downside it I am currently getting what sounds like the starter motor not engaging every time. It whirs well and vigorously like it is spinning freely. Restarting/resetting the ignition key off and on again allows the engine to turn over. So this is an intermittent issue.
2. I thought I'd do the engine oil swap while it is out of action and having other fluids changed. Letting it idle allows it to run for about a minute before it either chokes itself out or runs so lean it cuts out. I suspect I have moved the throttle cables out of whack. I'm doing some more experiments to see if I can get something more definitive to aid in identifying this issue. I have a few litres of fuel in there but might increase this to rule it out as lower than it would like.
Lawrence_NZ
Registered user
As it has started previously and sounds relatively healthy, I think all earths are in place. Two I recall, one on the starter motor and one on the left hand side engine block near the injector.
It is attached up until the middle of the bike and appears to be able to stretch to under the back seat or down to the side stand switch or for that matter all the way to near the handle bars...
My video footage of dissasembly is not useful as the only footage I have of it is me saying, Ï don't think this is plugged in". That led me to reinstalling everything up until the tank with a hope I was right and it isn't important. However, since someone spliced it, that now makes me think it might have a use. The additional female connectors are near the battery under the frame. There are two there I think it fits into. As there were shorter connectors that fit, I went with those expecting tighter lengths to be the more likely candidate.
Indicators are working and headlights/high beams.
Fully charged battery and attempting to turn it over this evening had no starter motor whirr but also no engine catching which again suggests fuel is an issue. I'll dump another few liters in tomorrow in case it is still too low but I'm thinking that is wishful thinking and the engine running was due to old fuel in the lines, now used up.
Wasnt the 1150 , partly due to the limited amount of engagement with the clutch plate & splines, and i believe there is a mod you can do to the clutch plate boss to overcome this ?
You may need to remove the fuel pump controller from the top of the fuel pump and “hot wire” the fuel pump to a battery to see if it whirrs. The FPC are known to be a weak point on these bikes.
It also sounds like your starter motor solenoid may need a clean if it is running the motor without it first engaging into the flywheel.
It also sounds like your starter motor solenoid may need a clean if it is running the motor without it first engaging into the flywheel.
Lawrence_NZ
Registered user
Happy to report that the fuel pump is working correctly and out of bike, attached to a 12v, it whirred nicely. It was actually lack of fuel.. Draining the tank for removal meant my refilling 3 or so litres just wasn't enough to keep it running. Adding another 5 or so litres made it all come right. No return of the starter motor spinning without engaging so assume this has now settled in after being disturbed in the disassemble and reassembly.
On refitting the fuel pump, I noticed a cracked plastic ring. I noticed this after filling anohter ten litres into the tank and hearing a torrent of fuel which came out of the top of the fuel pump opening.
A new plastic ring later and it was still leaking/weeping so assume this was me replacing/refitting the rubber ring around the top of the fuel pump and as it was a little mangled, I ordered another. Once that arrived and I lubed up the top of the fuel pump, it slid home without kinking and fuel leaks have stopped.
The mystery wire doesn't appear important as I never found a home for it. I also managed to remove another wire that powered the front accessory port as I must have pranged it while messing with the fuel pump causing it to short & smoke next to thte open fuel tank.
A tentative trip around the block up to 6th gear and back have me back on the road. Although it is now Winter so back on the road-ready for Spring. So many thanks for all the help and advice. Especially @Pukmeister who kept me at it and as well as providing the new-ish clutch talked me through the process. With the new oils the gear changes are smoother than they ever were.
In short, if your bike makes that sort of explody/crunchy noise and you lose drive, it is the clutch and can be replaced by an amateur in only 5-6 months!
On refitting the fuel pump, I noticed a cracked plastic ring. I noticed this after filling anohter ten litres into the tank and hearing a torrent of fuel which came out of the top of the fuel pump opening.
A new plastic ring later and it was still leaking/weeping so assume this was me replacing/refitting the rubber ring around the top of the fuel pump and as it was a little mangled, I ordered another. Once that arrived and I lubed up the top of the fuel pump, it slid home without kinking and fuel leaks have stopped.
The mystery wire doesn't appear important as I never found a home for it. I also managed to remove another wire that powered the front accessory port as I must have pranged it while messing with the fuel pump causing it to short & smoke next to thte open fuel tank.
A tentative trip around the block up to 6th gear and back have me back on the road. Although it is now Winter so back on the road-ready for Spring. So many thanks for all the help and advice. Especially @Pukmeister who kept me at it and as well as providing the new-ish clutch talked me through the process. With the new oils the gear changes are smoother than they ever were.
In short, if your bike makes that sort of explody/crunchy noise and you lose drive, it is the clutch and can be replaced by an amateur in only 5-6 months!
Great Work Lawrence and now you have really made it yours
Ready to Enjoy anytime you want (Y)
Only just noticed this thread, read it straight through. Very brave to take the job on at all but to actually complete it is quite something. The help provided was great too especially from Pukmeister.
Cool thread. Kudos to all the helpers and Laurence for sticking at it. Well done.
A great thread and as always loads of help on this forum. I've just read through as I'm doing the same job to replace what I suspect is a knackered damper on the input shaft. Thanks to all for tips and photos.
Been there, done that.
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