Just did stupid thing and took the bike along the road! Absolute mare got on the straight took the revs upto about 6k and went for it! Shit did it go, I soon ran out of road and had to keep revving it when I turned around, took off coming back and managed to look around at the exhaust and there was definatey more black smoke than normal coming out. Got to my turning and shut the throttle down engine cuts out. Starts again but only a small amount of revs were possible, even on full throtttle and no power. Had to push the bike home which hurt my broken bonesn no end! Got it back in the garage and it started again and let me rev it again? I am pretty worried something big is wrong but I guess until I swap the bits off the broken carbs that are coming into present one can't tell? Engine mechanicals sound lovely!

Ps. It has a true little horn racing exhaust on it and is very load! At the MOT I had an advisory saying " noisy exhaust " no marks or numbers on it, MOT man distcresion!

Any more comments and sorry no pics as I have to do all this on iPhone .
Mark

A good member has suggested that the inlet manifolds might be perished, anyone agree with this and are they still available?

It's unlikely but if you can start the engine spray some wd40 or carb cleaner on the inlet manifolds if the revs change then they could be gone.

I think your problem is a lack of back pressure caused by the exhaust lacking an exup (low down running) and the can affecting higher revs. The engine needs lots of fuel and air when it's like this and the carbs just aren't flowing it. This kind of home tune has left you with a huge flatspot (no power) if you take off the round top of the airbox with the snorkel (tube) attached is there an air filter ???

Will have a look, thanks

If you are right about no backpressure then what am I to do? Try the carbs first then move on to what? Could I stuff something up the exhaust?
Cheers mark

do many people agree about the backpressure point, am i wasting my tme and should just put a match in the tank?
Mark

the bikes were designed to use an exup, therefore they will need one as a standard bike to work properly. My race bike doesnt have one, but it has been on a dyno and set up accordingly, plus it never revs low enough to be an issue.
The best thing you can do is replace the silly end can, put in an exup and go to standard jetting. Then see if anything else needs looking at. From standard people know what the bike should do and can better advise on the things to try. There's no point trying this and that until you get to a base line that people know about and as it's been messed about by the previous owner, it gives piece of mind that it's been done properly!

I think i have another flappy bit of the exup valve somewhere and posibly a cover plate but can't be totally sure will have a look for you and see if you want them.

just on another note, do you have the exup motor connected?

Thank you, I would accept anything! the exup cables are still there and I think the servo is swell but I would have to look, the can on it is the only one I have so that has to stay!

Do you hear a weep weep noise when you turn the ignition on ??? that will the servo moving so it would be connected

I am absulty sure I used to hear it but am going to look tomorrow for it but before I changed the cdi I am sure I heard it everytime I used I turned on I heard it. I mean the cables are still there so I would think the servo is still there ? I am trying to buy those pipes with the exup from our nice forum member but waiting to hear back. Should I still do the carbs next as planned?
Thanks