RB 22 teething problems

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heliscoot
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Done 300 miles running an RB22, 35mm mikuni, nk pipe.timing 17 degrees. It's not been revving out but I put that down to the standard jetting making it run a bit on the rich side. Had jetting and needle changed now but still won't rev out just 'machine gun' noise and no increase in power. Also quite a bit of oil fuel coming back out of carb mouth. Was told my oil/fuel ratio at 4% was too much ie 200 ml for 5 litres told to reduce it to 3%. does run a bit better on acceleration but only goes up to about 55 mph until I have to back off the throttle. As I ve got a bit to go on the running in yet doesn't bother me too much but I'm just concerned if there is something else. Had it jetted (not dynoed) by local dealer but still same. Started off with 53 needle, 350 main,15 pilot. Now 56 needle (top slot), 300 main,22.5 pilot. Thought still better to leave fuel mix as per AF recommendation at 4%. Any advice appreciated. Cheers
rbgaz
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53needle did it even pullaway with this needle !!
jb tuning sets his up with a 58 needle 320 main and a 20 pilot (well he did mine )
300 miles u well an truely run in imo
y do u say u back off at 55mph ?

mine is now 57 needle 2 clip 360 main 27 pilot timing retarded as far as it will go nk exhaust
i spent 18months messing with mine as they can run very lean when crusieing, any lower on the needle than this mine is not rideable any higher and it blow hole in the piston ive also added a head gasket on mine to lower the comp
what gearbox u got ? mine is a gp 18/47 which is way to much and ive gotter change it its so revy its not nice i think af advice a 20/46 with gp box
sydduckett
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rbgaz wrote:53needle did it even pullaway with this needle !!
jb tuning sets his up with a 58 needle 320 main and a 20 pilot (well he did mine )
300 miles u well an truely run in imo
y do u say u back off at 55mph ?

mine is now 57 needle 2 clip 360 main 27 pilot timing retarded as far as it will go nk exhaust
i spent 18months messing with mine as they can run very lean when crusieing, any lower on the needle than this mine is not rideable any higher and it blow hole in the piston ive also added a head gasket on mine to lower the comp
what gearbox u got ? mine is a gp 18/47 which is way to much and ive gotter change it its so revy its not nice i think af advice a 20/46 with gp box
Enjoyed the run back from southend yesterday, even if we didnt quite catch john...lol
rbgaz
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yes nice ride, although i wasnt trying to catch john i was only quarter throttle lol
sydduckett
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rbgaz wrote:yes nice ride, although i wasnt trying to catch john i was only quarter throttle lol
I suspect its never been over 1/4 throttle.....lol
rbgaz
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o it has an 2 pistons later !!! lol prob is it gets upto speed with so little throttle in 4th it then runs lean im hoping when i change the gearbox i can open the throttle a lot further
heliscoot
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53needle did it even pullaway with this needle !!
jb tuning sets his up with a 58 needle 320 main and a 20 pilot (well he did mine )
300 miles u well an truely run in imo
y do u say u back off at 55mph ?

mine is now 57 needle 2 clip 360 main 27 pilot timing retarded as far as it will go nk exhaust
i spent 18months messing with mine as they can run very lean when crusieing, any lower on the needle than this mine is not rideable any higher and it blow hole in the piston ive also added a head gasket on mine to lower the comp
what gearbox u got ? mine is a gp 18/47 which is way to much and ive gotter change it its so revy its not nice i think af advice a 20/46 with gp box
the 53 needle was out of the packet carb job. Have to back off at 55 as its just noise, runs s**t
running italian GP box and also have kept 18/47, round donny is a nightmare with lights etc nice to be quick away even if you forfeit a bit at the top end, that said the more you get talking to compare all helps for a nice bike. 19/46 AF recommend I think may go that way when I upgrade the clutch assy next
rbgaz
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so u on a 56 needle now ? imo id say thats miles to rich mines a 230 and woudnt pull away even with a 56 needle

p.s when u say 55 are u talking about 4th or 3rd ?
at 55 on mine in 4th im just hitting the powerband and it just go and go with 47/18 its rev monster to much !!
heliscoot
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yep 56 it was set up by local dealer, that said ended up with reed valve petals blown to pieces after a backfire when podging with the jets, charged me 25 notes for the trouble and i had to get the manifold off : :?
55 in 4th i have to get thru the gears quick as it just seems to choke up when you give it some throttle just not getting onto exhaust at all.
i pulled plug he said it was spot on looked kin wet to me
rbgaz
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sounds like mine did when it had spilt a reed petal !!
it would just splutter and splutter just getting worse as time went on then started to backfire then died completly
the back fire was caused by every thing bening flooded the exhaust was full of petrol !!

but get a 58 and a 57 needle an see what happens they are pretty sensitive ive only got to rasie my needle by one clip and it will splutter big time
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