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cr750 Replica Carb settings starting point

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philward:
Hi Guys
Just got carb rebuild kit and before I put it all in, whats your views on main jet sizes and needle position settings - I'll be the cruzin image standard compression 836 big bore kit running bellmouths and the virtually straight through CR Rep 4 into 4 pipes. I know that I will have to experiment with settind but just looking for opinion on initial starting settings.
My standard K2 with standard airbox/exhaust runs standard settings with same 836 piston kit.
Thanks
Phil

Bryanj:
At a guess up 2 or 3 sizes onmains and work from there

MarkCR750:
I think not using the standard air box on the CR will make a big difference, I've got modified K&N type pod filters on mine (grafted the rubber inlet trumpets from the standard air box into the K&Ns to get a smooth airflow into the PD41A carbs), a 4 into 1 exhaust, I've gone up to 135 mains , standard primary's, I get a good plug colour and no flat spots, every set up is of course going to be different though.

philward:
Thanks Guys - just occured to me that Simom Tappin (Moonpie) who provided exhausts would probably have a good idea as he run one with similar set up - so have emailed him.
Thanks again

philward:
Emailed Simon Tappin who only has data on CR race carbs but recomended I speak to Allens Performance (Nottingham) - he says they are really knowledgable and might even be able to make recommendations. Had a look on their website and looks very useful. Forum members may already know them but thought I'd post the link for future reference.

http://www.allensperformance.co.uk/carb-kit/keihin-jet-identification-chart/

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