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Won't pull pass 6500 rpm
Gav - 7/7/09 at 03:38 PM

893 Blade wont pull past 6500 under load, i had to lean the mixture out for SVA but i've put it back to where it was and it still wont pull.
just using pipercross filters as i couldn't fit the original airbox on due to the cradle.
Any ideas?


speedystew - 7/7/09 at 03:58 PM

i know exactly whats up

you need to block off the middle air corrector and put a dynojet kit in it


andrew.carwithen - 7/7/09 at 03:59 PM

Have you dynojetted it or are the carbs still fitted with standard jets?
Are the carbs balanced?
Mine wouldn't pull beyond 5000rpm with standard jets and sausage filter.
Fitted a dynojet kit before SVA as supplied by Andy at AB performance with 132 mains, replacement needles set to his spec and air pilot jets blocked off (the tapered part of the old needles are ideal for this)
The transformation was incredible!!
Pulls all the way through to the red-line and beyond with no flat spots at all.


Gav - 7/7/09 at 04:04 PM

Cheers chaps.

No dynojet on these carbs, i have the original carbs what came with the engine but are a bit mucky, they were dynojetted but for the original airbox, any way i can check what the needles are, that are in them?

Are the air pilot jets the 3 little brass nozzles that sit below the intake trumpets?

[Edited on 7/7/09 by Gav]


speedystew - 7/7/09 at 04:09 PM

the three little brass nozzles are the air correctors you need to block off the middle one but in doing so it won't work with the airbox again


Gav - 7/7/09 at 04:14 PM

Cheers


andrew.carwithen - 7/7/09 at 04:44 PM

quote:
Originally posted by Gav
Cheers chaps.

No dynojet on these carbs, i have the original carbs what came with the engine but are a bit mucky, they were dynojetted but for the original airbox, any way i can check what the needles are, that are in them?

Are the air pilot jets the 3 little brass nozzles that sit below the intake trumpets?

[Edited on 7/7/09 by Gav]


Errr.....you're not getting the air pilot jets confused with the external brass take-offs that are used when attaching carb balancing gauges are you?
Have a look at http://www.zen69595.zen.co.uk/carb.htm which explains how to fit a dynojet kit. (though as I said before, just use sections of the old needles to block off the air jets rather than drill and plug them. Saves getting any swarf in your carbs! )


Gav - 7/7/09 at 04:50 PM

ah thanks for the link, i'll be ringing andy bates and ordering a dynojet kit then


speedystew - 7/7/09 at 04:53 PM

the last picture is the blocked off air corrector,but my dynojet kit from holeshot came with the bung and you didn't have to mess about drilling it,just glued it in 115 bhp@ wheels on holeshots rolling road


Andy B - 7/7/09 at 05:18 PM

Hi Guys
just spotted this thread - advice given so far is spot on - on standard carbs the motor is going massively lean and struggles to pull through 5000 upwards.
Our recipe for the RGB motors is as follows -
standard blade fuel pump - definately not facet with regulator or it will overfuel like a good 'un
Fit a dynojet kit but ignore the settings and instructions from dynojet otherwise they will have you drilling slide lift holes which you definately dont want to do, with the added weight of a bec the slides are already moving too fast.
If you need a jet kit I have them on shelf but with jets for bec not bike, I can send you one with a complete set of install settings which should pretty much give you a screamer straight away, should be no need to dyno as we have already spent 16 hours on one to get to these settings and unless the pipe is totally wrong it will work.
If you need any help give me a call on 01449 736633
regards
Andy
AB Performance


GeoffB - 7/7/09 at 06:07 PM

also make sure you have not joined togeather the pipes that sit on the exhaust side of the carbs they are some sort of breather tubes..mine hand brown platictic pipes and a t piece on and i connected back togeather and put them into the airbox and it would not rev pas about 6-7 k no matter what jets,needles or whole that i blocked off..i think there are pics in my file but let me know if you get stuck