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carb jets

Posted: Sat Jan 16, 2010 10:43 pm
Author: walshyco
I searched the forum for the answer to this but couldn't find it I'm sure it must have been asked before, but here goes I am putting a second hand harris 4into1 onto my Z1B [standard pipes are for sunday best not for sale sorry] do I need to re-jet if so can anyone tell me jet sizes I will need, and the best place to buy the jets from. Thanks in advance. Sean.

Posted: Sat Jan 16, 2010 11:33 pm
Author: paulmceleney
no should be okay

Posted: Sat Jan 16, 2010 11:43 pm
Author: m1ks
Most likely will be fine as most performance 'road oriented' pipes are not too far from the standards as regards operation and gasflow.
However, if they are most definitely full performance with minimal baffling the general rule of thumb is to increase main and pilot jets by 10%, i.e. running 100 mains, fit 110 mains.
Best thing to do, fit the pipes and remove and thoroughly clean your plugs, get it running temp warm and check mix with a gunson colourtune, if you don't have one or access to one then just go for a good run, half hour or more, check plugs on return, if they look OK keep checking them over a week or so, if they show signs of running lean try adjusting your needle and enriching the pilot mix screw 1/4 - 1/2 turn.
If they still look lean after another week of running and checking, (again assuming no colourtune), then look at rejetting.
Obviously, if they continue to look OK over a week leave em alone, all's well there.
Additional to this if you fit pods typically a further 10%| increase will be required, these figures are approximate rule of thumb, if you want to get it properly set up, take to a tuners with a dyno and do what they tell you.

Then post the dyno chart on here to show off :D

Posted: Sun Jan 17, 2010 12:43 am
Author: sweptail
mine ran great with 120 mains in on a Harris

Posted: Sun Jan 17, 2010 11:30 am
Author: hillbilly
i had 122.5 in my z1b.ran well.everyone is different.good luck.

Posted: Sun Jan 17, 2010 9:36 pm
Author: walshyco
Cheers for your help lads, Much appreciated.I know what i'm gonna be doing on my next day off. :hoo