alternative carbs ?

[DiverRay]

The XS IS clunky! It needs to be shifted like a tractor, clutch in all the way and a FIRM up or down shift. Not like the R1200RT or Kawasaki Concours.

[Tonyxs11]

The XS IS clunky! It needs to be shifted like a tractor, clutch in all the way and a FIRM up or down shift. Not like the R1200RT or Kawasaki Concours.

yeah its been a long time since my last eleven, and when on it today it brought it all back to me what didn't help was the gear lever was too high, but after adjusting it down it felt better.

[LAB3]

For what it's worth I find that it shifts like a powerful, fast bike should at 7k RPM, much below 5k and the tractor analogy rings true.

[Tonyxs11]

after quite a bit of fettling ive got it to run pretty good now, the diaphragms where replaced which helped as i found small holes in 2 of them. still not perfect but a bit of fine tuning should sort it.
still got the tank and the front wheel to paint and replace the seat cover (if I ever find one ??? ) but its got really cold over here so their won't be much work going on

[Tonyxs11]

well still got an intermittent stumble between 2500-3500rpm !!!! above that it pulls great. I haven't got the vacuum advance connected because of the FJ carbs but others that have fitted them say they didn't need it. will do more fettling after Christmas.

[LAB3]

Here's how I see it. The engineers at a manufacturing company have more experience at what it takes to make an engine run than I do, if they see fit to put an advance mechanism on an engine then who am I to say otherwise?

[Tonyxs11]

Here's how I see it. The engineers at a manufacturing company have more experience at what it takes to make an engine run than I do, if they see fit to put an advance mechanism on an engine then who am I to say otherwise?

yep I agree, but after reading other people who have fitted other carbs said they didn't have the vacuum advance connected, also I have a mate who has an XS11 who has Kawasaki carbs on his with no vaccum attached. ive checked the mechanical advance and it in good order. will check the timing at some point.

[DiverRay]

The vacuum "advance" on the XS11 is also a retard for the timing. It is the reason you can put this bike in 5th gear at 25mph, and just twist and go. You will lose a little of that without the vacuum set-up.

[Tonyxs11]

The vacuum "advance" on the XS11 is also a retard for the timing. It is the reason you can put this bike in 5th gear at 25mph, and just twist and go. You will lose a little of that without the vacuum set-up.

the strange thing is I can set off from idle and wind it on right through the rev range no problem, and then it'll struggle at around 3000rpm ????

[bikerphil]

Try changing the needle clip position, lower it for more fuel. Maybe those would need a shim instead. Also check that there aren't any worn spots on the needles, that would make it soggy around 3K.

[Tonyxs11]

Try changing the needle clip position, lower it for more fuel. Maybe those would need a shim instead. Also check that there aren't any worn spots on the needles, that would make it soggy around 3K.

ive already done that Phil, ive had the needles in every position and different mixture screw settings. the needles (and the carbs) are in very good condition, the thing is sometimes it revs clean right through ??? thats why i wondered about the vacuum advance. its not a misfire and the coils tested perfect, new plugs and NGK plug caps.

[DiverRay]

On the stock carbs, it's the pilot jets that cause the problem. Try going up one size on them.

[Tonyxs11]

On the stock carbs, it's the pilot jets that cause the problem. Try going up one size on them.

I dont think that will help, the pilot jets in these carbs is the same size as the XS carbs. when the stumble happens i tried pulling the choke out different amounts and it just got worse. so it says its running rich !!! as I said though it doesn't happen every time.

[bikerphil]

Maybe try using the XS needles and maybe also the emulsion tubes. Sounds like you've tried just about everything else. Having the vacuum advance not connected shouldn't cause a rich condition. I've run them that way for a time without an issue. When I experience a running problem around 3K, I always suspect the fuel needles. That's the range where it begins to transition from the low to high speed jets.

[Tonyxs11]

Maybe try using the XS needles and maybe also the emulsion tubes. Sounds like you've tried just about everything else. Having the vacuum advance not connected shouldn't cause a rich condition. I've run them that way for a time without an issue. When I experience a running problem around 3K, I always suspect the fuel needles. That's the range where it begins to transition from the low to high speed jets.

yeah my thought was the needles too, had them in every position but didn't sort it !!!!! off idle it pulls great till 2500rpm then the stumble till 3500rpm then it pulls great again. the strange thing is it doesn't always do it ? will do more digging after christmas just can't be bothered right now as its just far to cold