The belt and stand switches shouldn't affect the idling of the engine, they just prevent the engine revving if the stand's down or the belts aren't plugged in. So the stalling won't be connected directly to the stand or belts.
Have you already checked for an air leak round the injector?
Have you done the checks for an air leak around the fuel injector?
Because we don't see large gaps usually we don't know how that would affect the engine running. Normally as the engine warms up the valve stem increases in length, which reduces the clearance. In your case the engine running should actually improve as it warms up because the gap would be reducing closer to the spec for a cold engine. That would mean that the exhaust valve would not be opening quite enough for best performance, but I wouldn't expect it to make the engine stall. I think you should still set the gaps to the correct ones, you may not need to buy new shims, there are quite a few people with the larger sizes lying about, myself included. I can have a look for a couple for you if you need them, let me know.
The only other cause I've seen for one of these engines to stall as it warms up was when the crank was seizing, but this happened within one minute of starting it from cold and it was a very sudden stop each time. I don't think this will be your problem though.
Agree it’s unusual to get a larger gap than spec on the exhaust valve. In this case you need 0.05 thinner bucket which means you need a 2.70 bucket instead of a 2.75. That would give the maximum clearance which is the safer end of the range.
100% sure. If you disconnect the battery when it’s running it will stop immediately. If you jump start with a dead battery it will stop as soon as you disconnect the jump leads. No idea why, maybe related to fuel injection cut off as a safety feature?
The engine will not run with a dead battery
I remember reading about this kind of uneven pad wear being a problem many years ago. Some of it was due to the pad retaining pin holes wearing, but maybe the wear you've seen was also a problem. I think Lawrie made up some bushes to insert in the calipers, once the holes had been drilled round again. Maybe a search will reveal something. Don't forget to spell caliper with one L though!
I'd like to join that trip. All I need is an invitation from the curator, a nice guy called Paul I think. Oh hang on .......
A nice idea to keep a pristine C1 in pristine condition! Sorry to see you giving away your last one, but I guess it will come to most of us at some point. Mine only does about 500 miles a year now, unless I go to the Treffen on it, when it does an extra 1000 miles. So with no Treffen this year it won't get used much. I've been renovating a Matra Murena car for the past 9 months, instead of my usual pastime of renovating C1's, so I don't spend as much time on them these days. They are a lot easier to maintain than 37 year old cars!!
Keep in contact with us, I'm sure your experience will be useful to less experienced owners.
I always have them balanced when they're fitted, it costs very little extra and eliminates the thought that this could be the cause every time you feel a vibration. Wheel weights are nearly always required, so the balancing has a benefit.
You will also need to take out the crank and sort out the conrod to crank bearing. Even if it seems to be rotating when cold you may find it seizes whenever you start the engine. I've got a spare parts engine which was doing exactly this. The repair requires a press to get it apart, then you have to source the parts, so in the end I found it cheaper to buy a write off with a good engine.
I can confirm that 4 years later my C1 still has no coolant leak into oil problems. Like yours, my C1 was not used for a few years, during which time the outside of the water pump corroded and let coolant into the oil. Maybe I'd put the wrong antifreeze in at some point in the past and it allowed a bit of corrosion. If you replace the large o rings it should be ok, I replaced the whole pump because I had a spare.
Another example of how c1s deteriorate if unused, along with shock absorbers, fork seals and stand mechanisms in my experience.
Did you find a refurb kit for the piston seal etc as well?
Well done Pat! I can see a few potential problems but a good start. You must be getting a bit bored I suspect ????
You have to prize them off and they're quite brittle, so some break. The best way to make them less brittle is to warm them up in some way: sunshine / hair dryer / hot air gun etc. Then gently work a screwdriver in from the outer edge and slowly undo each one. Good luck!
Could be a weak spring on the sprag clutch if the starter sounds like it’s losing connection with the engine while trying to start it.
I’ve tried Bridgestone Battlax tyres on the fronts of 2 C1 s and found them to be good. They were described to me as the next development of the Hoops and I would say that’s reflected in their performance. I haven’t tried them on the rear yet.
I can’t see that famous front mud guard or the top box. I’ve got an old battered top box if you need one ;-)
Looks superb, and ready in time for the NEC. I hope to see it at the bike show.
I think the guys who refurb them use methylated spirit and fine wire wool to remove the coating.
I’ve fitted them a couple of times, they’re more robust than the BMW ones and hotter. The last ones I did were their “scooter” grips which use less power but are still warm enough. You always have to do some sanding of the throttle handle tube and superglue it to the throttle twist on the bike. The glue comes with the grips. Not too difficult but just be aware some modification is needed.
Very smart Paul! Should protect the vulnerable electrics at the front of the bike. I won’t forget the smile on your face when you got that mudguard!
The speedo is working fine without the dash bulbs, but I suspect they were removed because they were constantly on, why else would you remove them? However I’ll refit the bulbs and see what happens.
I'm seeing more failed ABS pumps on C1s these days and they don't lend themselves to amateur refurbishment, so used ones at around £100 + seem to be the best option, unless anyone knows of an alternative?
I've been researching the code numbers printed on the C1 pump: 310 000 20050 and 3451-2 335805. They seem to be unique to the C1, but the BMW F650 GS (2002) has a pump with codes 310 000 20040 and 3451-2 335804, which are very similar and photos of the F650 pump look identical to the C1 pump. Has anyone seen an F650 pump used in a C1 e.g. on the German or Italian forums?
There are more F650 pumps about so they're nearer to the £60 mark second hand. It would be good to have another option.
Obviously the dash bulbs on a C1 can be removed and the rear sensor also, to make a bike look externally as if it never had ABS, and the brakes will function perfectly well as non ABS brakes. But if possible I like to have everything on a bike working as it should, if parts prices are justifiable.
I’ve never noticed that bolt before. It’s worth undoing and having a bit of a go at removing the bottom part I reckon.
I didn't realise they're "classics"! As I'm only 5 miles away from the NEC the previous day I might just stay over and call in on the Friday.
Assuming you’ve got the correct sized O ring in now, you can either seal the large ring with sealant or build up layers of a suitable tape on it to help it seat better. I use self amalgamating tape.
There’s a metal flap, accessible through the hole where the levers come through the dash. With a bit of practice you can move this manually as a temporary measure, it might be causing your problem. Longer term you would need to remove the 2 bolts which hold it in and grease everything properly. I’ve never had any luck with fixing the stand mechanism with just a squirt of WD40.
I have a couple of used stand mechanisms with shock absorbers in them. Send me a private message if you need one. I live in Manchester so factor in some postage.
Sounds like the sort of bike I’d buy for a renovation project! They all sound like common problems. The coolant loss may take some finding as I’ve found various reasons from chafing pipes, corroded alloy pipe, water pump etc. The top box can be modified to fit securely, so don’t throw it away. Good luck!
They certainly need a bit of persuasion! My worry is that they will crack, a bit of a common fault, so far I’ve got away with no cracked ones.
Compression sounds ok, so head gasket may be ok as well. If the coolant problem is settling down try running the bike round for a few days and monitor the header tank and sometimes the filler cap level.
You shouldn’t get vibration through the handlebars. Check front tyre and wheel for damage. If it’s at certain speeds get the wheel balanced. After that you could check the front forks for signed of leaking or even remove them and check if they have oil in. They will help to damp vibrations if working properly I guess.
I tried the standard BMW FAS yesterday. It works ok but the speed sensitive volume is linked to engine revs instead of bike speed for some strange reason. Every time you back off the throttle the sound goes quiet, then when you open up again the volume goes back up. So riding in traffic at varying throttle openings renders the FAS useless at best and irritating at worst.
The Boombox on my other C1 has no speed or revs sensitivity and is a far more successful setup. It also has better sound quality, although the FAS sound quality is not bad, when you can hear it. Maybe it would be possible to cut the wire which supplies the revs signal to the FAS?
If you can get hold of the proper C1 speakers they are good, but from what I’ve heard the FAS amp is not good. In fact I’ve got it on one of my C1s and never bothered to try it! I must give it a go next time I’m out on it. My other C1 has the BMW speakers connected to a 40 watts per channel Boombox and they handle the power very well, they sound good.
You usually have to reduce the size of your pictures as well. A bit of a PITA I find.
Check the valve clearances and adjust if necessary, much easier with the engine out. I recently had a lower cylinder gasket leaking, a cheap part but engine dismantle required to replace it. Piston ring compressor useful for this job. Water pumps do wear out, not a big problem to replace with the engine in the bike.
I get head gaskets from BMW, I've not found an alternative. Make sure you order one for the right engine size.
It's an engine out job as far as I'm concerned. Getting it out isn't such a huge job as long as you don't come up against corroded exhaust nuts or similar types of hurdles. Once out all jobs on it are so much easier.
You'll need a torque wrench and a way of tightening the head nuts, which are difficult to access. For the inside ones I use a small socket set of decent quality, which will stand the torque. For the external ones I use a swivel headed double ended ring spanner of decent quality, and attach the torque wrench to that when it's 90 degrees to the nut.
The brake light problem sounds like at least one of the micro switches on the handle bars has got stuck. Try pressing the switches in and out and listen for a click, which implies they’re working. Or use your meter to check their continuity if you can get access to their plugs. Replacements are cheap if you look around, but they would need the plugs soldering on. Alternatively BMW will supply them probably at top dollar prices with the right plugs on.
Opening up the alternator to get to the yellow wires is a bit involved and may require a new gasket, but it’s not very difficult. Once in there, repairing the wires will need some good soldering to avoid them breaking again.
Try a Gunsons compression tester with suitable adapter for the spark plug size. If the head gasket is leaking it will soon let you know. Compression needs to be at least 11 bar, preferably 12 plus when turning the engine over on the starter with a good battery. If your engine is turning over slowly you may need a refurbished starter motor or better battery before you can get a proper compression reading.
Possibly head gasket? If it’s leaking from the cylinder into the coolant system the compression will push air into the coolant. A compression test could help diagnosis.
I know brake pipes can be fabricated fairly easily by specialists with the right flaring tool for the ends, so maybe the same brake specialists can make up hoses. You could go all flash and get a braided hose made up!
Variobob told us that methylated spirit and fine wire wool are what they use to remove the old rubberised paint. Oh, and lots of elbow grease!
I had a slight thrum on my C1 before riding it to Germany in June. After 1000 miles it has almost gone. The wheels are both balanced, so I assume it was drive belt related, anything else would probably have got worse.
Where’s the fun in that? I like a challenge!
Well, everything ran fine through the winter, the idling settled down once the injector seals were done and the exhaust was properly tightened. The Datatool alarm has been removed, so now I can go near the bike without it deafening me!
All was well until 4 or 5 weeks ago, when the dreaded ABS lights came on again! I threw the bike in the shed in disgust and concentrated on getting the other C1 right for the trip to Germany. Now I'm back, so today I got round to taking the panels off to look at the ABS pump I replaced 18 months ago. In that time, water has found its way into the electrical plug and completely corroded away 2 of the 4 larger pins and started corroding other pins in there as well!
The pins are impossible to replace and their residues are inside the big plug, so that's useless as well. So the plan is to take the ABS plug off a spare wiring loom I have, solder it into the bike's loom and source a second hand pump. I'm not sure how the water got into the pump, but I'll be looking at shielding it with plastic to protect it from front wheel spray. Ideally a mud guard should be fitted as well to keep the water away.
I saw Variobob in Germany and he kindly gave me some hints about ABS problems. Apparently the wiring loom can short against the frame, but it's quite difficult to spot, so requires undoing the clamps and pulling the loom away from the frame to look at it properly. In my case the fault is obvious this time, but I'll be checking the loom for future problems anyway.
I'll keep you updated, just in case someone else gets ABS problems. It's a labour of love though!
Looks interesting, and expensive...
If it ever reaches the market, I'll wait a couple of years after launch to see if prices go the same way as C1 prices went! I jumped in too early with C1s and paid top dollar!
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