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...i knew it wasnt going to be pretty given the hard life it looks to have had, and the fact that the chain has over 60mm of slack...but 54.14bhp...im embarrased to put it up, ill upload the dyno trace tomorrow at work.

fuelings good slightly rich at ~5k rpm, then a tiny bit lean throughout the rest of the rev range, ill get him to drop the main jets slightly, that should richen it up a bit.

for christmas it is getting, new exhaust can, new sprockets and a new chain...60mm...it actually hits the swingarm and still could go further...

Update - The trace

banner001 wrote:, ill get him to drop the main jets slightly, that should richen it up a bit.

for christmas it is getting, new exhaust can, .

You're doing it the wrong way round. If you stick a new can on it it will most likely upset the fuelling (not as much as a full system but it will still have an effect). So if you tinker with the carbs now, then change the can, you could be back to square 1. Put the can on, stick it on a dyno again, THEN adjust the needles if required. Always do a dyno run AFTER you've modded any part of the inlet / exhaust combo.

Have you been in the engine to check valve clearances? Have the carbs been balanced? Even with a worn chain 54bhp is pretty dire and suggests it could do with a damn good service.

Tirpitz wrote:

banner001 wrote:, ill get him to drop the main jets slightly, that should richen it up a bit.

for christmas it is getting, new exhaust can, .

You're doing it the wrong way round. If you stick a new can on it it will most likely upset the fuelling (not as much as a full system but it will still have an effect). So if you tinker with the carbs now, then change the can, you could be back to square 1. Put the can on, stick it on a dyno again, THEN adjust the needles if required. Always do a dyno run AFTER you've modded any part of the inlet / exhaust combo.

Have you been in the engine to check valve clearances? Have the carbs been balanced? Even with a worn chain 54bhp is pretty dire and suggests it could do with a damn good service.

where did you take it for a power run and price please

sorry tirpitz, ment to say if i wanted to get anything done there and then, thats what i would have done.

ill be mothballing it over christmas, but i wont be able to work on the bike, im looking at leaving it in the garage until the end of january, ill got some maintenance done on it then. ill take the carbs out, give them a clean (we have several sonication baths and probes at work, ill dump it in some petrol and give it a sonication clean), replace the shims, i cant check vacuum's as i dont have a gauge, and ill whip out the spark plugs too...but the chain is seriously shagged, it rattles about like nothing, i can hear it slapping the swingarm which cant be good ill post up the trace tomorrow its at the top end it really is but at least its generally smooth and the fuelling seems ok, that was my main concern.

if not i know mark white from PB mag, ill take it over to him.

as for the dyno run i took it to Jordan bikes in leeds when i was home, i rang up a dyno place in taunton i think but they were fully booked until february...couldnt be arsed to wait that long

Jordans have got a good rep so you should be safe there. If you take it for another run there next year when you've done all you want to on the bike then they will fettle it for you. Don't worry about not having gauges as if you're going to get a dyno place to fettle the bike you can ask them to do you a carb balance while they're at it and get everything set up sweet in one go.

im tempted just to buy a set of gauges, they are the cost of 1-hour service and i would like to learn how to do it. and if ive already replaced the spark plugs and checked the shims i might as well vacuum check the cylinders too...

ok thats the trace posted above...my it looks dodgy

hmmm im starting to think the bike is restricted, thats why the bhp is so low, it wont go above 10k rpm in 6th gear, will have to get myself out at night and give it a run, see what rpm/mph it pulls to in every gear.

new headers/downpipes, new camchain, new tensioner, valve clearances sorted, bike feels different, but exactly the same top end, 54.16bph and i noticed that going from 4th gear to 6th gear at 100mph+ the needle wavers about until it settles out at ~10k and wont go any higher. need to see what it will do in 4th and 5th, it revs up to over 14000rpm fine in 1st, 2nd and 3rd gear though, so is the restriction dependent on which gear you have the bike in?

i.e. 1st to 4th gear you can rev to redline, so 14800rpm
5th and 6th it restricts you to a particular rpm, say 10000rpm??

cheers

banner

ps, might also explain the weird "saw-tooth" bit at the end, no-one else's seems to have this...