main jet, needle position for mods?

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nz_gixxer4_racer
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Re: main jet, needle position for mods?

Post by nz_gixxer4_racer »

TeamGSXR wrote:SU-7592 K&N.
Scorpion race can.
GK76a SP.

I'm in the process of setting up the carbs. Standard main jet is 100. I'm going to try 112's and drop the needle by one.

I checked the archived section of the forum. Others were running 112's or 114's main jets. Stripes recommended starting at a 120 main jet and coming down. Or starting at 110 and going up...
By drop the needle, you mean dropping the clip ie, raising the needle to give it more fuel?

If so, that would be good place to start. on the 100 mains, I raised the needle 2 clips. When I put in bigger mains, that needle position would be too rich no doubt, so may drop it 1 clip.
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Re: main jet, needle position for mods?

Post by Variablevalves suck »

No, i dropped the needle/rased the clip as the bigger main was fuelling to much in the mid range/part throttle.
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Re: main jet, needle position for mods?

Post by TeamGSXR »

Variablevalves suck wrote:Hi J,
120's sound big, You will be close with the 112's and if the bottom end gets boggy you may need to up the pilots a couple.
Hi Chris! How's the bike coming along?

Yeah I thought 120's seemed mahoosive. When it was on dyno I know it was running slightly lean. More so below 8k though as the curve was all over the place. Hopefully can improve on the 58bhp and get it running so it's useable!
nz_gixxer4_racer wrote:Hi there!
How is the archived material accessed? Having searched the current site, nothing came up. I take it this is a recently "revamped" site?
Hi... Yes the site went through a change. Archived section = http://www.crm250.com/400greybike/forum/default.asp" onclick="window.open(this.href);return false; - theres some useful info stored on there.
nz_gixxer4_racer
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Re: main jet, needle position for mods?

Post by nz_gixxer4_racer »

TeamGSXR wrote: Hi... Yes the site went through a change. Archived section = http://www.crm250.com/400greybike/forum/default.asp" onclick="window.open(this.href);return false; - theres some useful info stored on there.
Shame, but I cant access the technical section as I need to be logged in, and joining has ceased.
Pitty...
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Re: main jet, needle position for mods?

Post by Variablevalves suck »

The bikes about 98% there, got the wiring loom back on but am waiting for some oil lines for the VV control and they aint appearing! :cry: otherwise it should fire up.
Any about 75% with the full exhaust system!
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Re: main jet, needle position for mods?

Post by gsxr400 racer »

115 on my FCR flatslide 33mm carbs 442 and full pipe no air filters as of yet :mrgreen:
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Re: main jet, needle position for mods?

Post by TeamGSXR »

nz_gixxer4_racer wrote: Shame, but I cant access the technical section as I need to be logged in, and joining has ceased.
Pitty...
Ah sorry! If you want me to look anything up on there give me a yell. The jet info is pretty much covered here now tho.
Variablevalves suck wrote:The bikes about 98% there, got the wiring loom back on but am waiting for some oil lines for the VV control and they aint appearing! :cry: otherwise it should fire up.
Any about 75% with the full exhaust system!
Excellent mate. Not too long now then (hopefully the oil lines will magically appear soon!). What are your thoughts on running the standard pilot jets (47.5's on mine)? I remember Stripes saying with the K&N and an end can they are fine as standard? I guess the obvious way is to try it...
gsxr400 racer wrote:115 on my FCR flatslide 33mm carbs 442 and full pipe no air filters as of yet :mrgreen:
^^^ show off :P :mrgreen:
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Re: main jet, needle position for mods?

Post by nz_gixxer4_racer »

ive decided to start on 115's with pretty much open box and open pipe with the gk76 400 ( :oops: )
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Re: main jet, needle position for mods?

Post by Variablevalves suck »

nz_gixxer4_racer wrote:ive decided to start on 115's with pretty much open box and open pipe with the gk76 400 ( :oops: )
You will have to up the pilotjets or it will massively bog when you open the trottle.
James, you should be good on the standards and Jay, im suprised your not running bigger jets with your carbs as they flow more air than the standard CV's, you got that GSR motor yet?
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Re: main jet, needle position for mods?

Post by gsxr400 racer »

No gsr motor yet waiting for it to get to Cali. from japan but i got the wiring harness, CDI and throttle boddies

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