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Offline bikoholic

Another jetting question
« on: October 11, 2013, 02:52:45 pm »
My bike is standard except for a aftermarket slip-on.  I want to open the air box and change the jetting.
Do I then raze the needle one notch?
What size pilot and main jet do the Gauteng people use after opening the air box?

I would really appreciate some help.
 
Who needs a road anyway?
 

Offline LouisXander

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Re: Another jetting question
« Reply #1 on: October 11, 2013, 05:29:38 pm »
Pm Ganjora Johan, hy sal weet
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Offline Noobie

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Re: Another jetting question
« Reply #2 on: October 11, 2013, 09:56:32 pm »
My bike is standard except for a aftermarket slip-on.  I want to open the air box and change the jetting.
Do I then raze the needle one notch?
What size pilot and main jet do the Gauteng people use after opening the air box?

I would really appreciate some help.
 

Hey Bikokolic, will be keen to find out how you get along here as I would also like to remove the air box cover on my DR650

I put on a powerflow exhaust on my bike and then the header pipe got red hot in just a few minutes of light riding, the guys on the forum said it was running "lean" so I took the carb apart and moved the C-Clip on the needle down 2 notches - which in turn raises the position of the needle within the carb chamber and it sorted it out perfectly

I will be watching this thread to see who can advise as to the correct jets, good luck :thumleft:

I have ordered a jetting kit from procycle and a performance air filter, once that arrives I will have to fiddle with the jetting again!
'90 TS125, '85 XT500, '07 CRF250R, '10 DR650 '79 CB650
 

Offline bikoholic

Re: Another jetting question
« Reply #3 on: October 14, 2013, 11:23:14 am »
I took the needle out and the c clip was in the 2dn clip from the bottom, I then moved it down to the last clip from the bottom (raising the needle). There is also a white round plastic spacer thing that fits under the c clip. Is this white plastic standard? Opened the air /fuel screw 1 and 1/4 turn out it was 2 turns out. Now the bike back fire on de-exhilaration. Am I running to rich now?
Who needs a road anyway?
 

Offline Noobie

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Re: Another jetting question
« Reply #4 on: October 15, 2013, 07:32:05 pm »
I took the needle out and the c clip was in the 2dn clip from the bottom, I then moved it down to the last clip from the bottom (raising the needle). There is also a white round plastic spacer thing that fits under the c clip. Is this white plastic standard? Opened the air /fuel screw 1 and 1/4 turn out it was 2 turns out. Now the bike back fire on de-exhilaration. Am I running to rich now?

If its backfiring on deceleration than its probably running rich, have you taken off the air filter box side cover and leaned the air filter?

The white plastic spacer is standard
'90 TS125, '85 XT500, '07 CRF250R, '10 DR650 '79 CB650
 

Offline bikoholic

Re: Another jetting question
« Reply #5 on: October 23, 2013, 07:04:01 am »
After allot of fiddling around. Airbox lid open then closed then needle up and down then lid closed then snorkel off then back then needle then fuel screw and and and a lot of testing I ended up with standard pilot jet, 150 main jet, needle in the last clip (raising the needle), snorkel removed and 8 x 10mm holes in the top of the airbox.  Very happy, the bike pulls nicely, no surging at all and 21km/l traveling to work and back.  :thumleft:
Who needs a road anyway?
 

Offline Noobie

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Re: Another jetting question
« Reply #6 on: October 23, 2013, 07:40:46 pm »
After allot of fiddling around. Airbox lid open then closed then needle up and down then lid closed then snorkel off then back then needle then fuel screw and and and a lot of testing I ended up with standard pilot jet, 150 main jet, needle in the last clip (raising the needle), snorkel removed and 8 x 10mm holes in the top of the airbox.  Very happy, the bike pulls nicely, no surging at all and 21km/l traveling to work and back.  :thumleft:

Wow, that sounds like loads of work! Its definitely a labour of love :thumleft:
'90 TS125, '85 XT500, '07 CRF250R, '10 DR650 '79 CB650
 

Offline lecap

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Re: Another jetting question
« Reply #7 on: October 24, 2013, 08:44:55 am »
FYI backfire on overrun is a tell tale sign of an engine running LEAN!
"If you think it's expensive to hire a professional to do the job, wait until you hire an amateur." (Red Adair)
 

Offline Woestynhond

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Re: Another jetting question
« Reply #8 on: November 23, 2013, 10:23:24 pm »
Running lean as lecap said...not good but they do come like that from the factory!
 Running too rich will also cause problems like cylinder lining/plating whatever to wear faster.....and your budget will also wear a lot faster........
and she said " What are you doin today ? ".
and I said " Nothing ".
and she said " But you did that yesterday ".
and I said "I haven`t finished yet ".
 

Offline bikoholic

Re: Another jetting question
« Reply #9 on: November 25, 2013, 09:35:17 pm »
After allot of fiddling around. Airbox lid open then closed then needle up and down then lid closed then snorkel off then back then needle then fuel screw and and and a lot of testing I ended up with standard pilot jet, 150 main jet, needle in the last clip (raising the needle), snorkel removed and 8 x 10mm holes in the top of the airbox.  Very happy, the bike pulls nicely, no surging at all and 21km/l traveling to work and back.  :thumleft:
and no more backfiring :thumleft: air screw 2 turns out.
Who needs a road anyway?
 

Offline Woestynhond

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Re: Another jetting question
« Reply #10 on: November 25, 2013, 11:14:51 pm »
Standard needle? Did you have the DR air / fuel ratio measured? What brand name of jet? Does it lift its front under acceleration in 1st? :ricky:

 Different makes have different ways of measuring their jet sizes so to speak! example: a dynojet 160 will be equivalent to a mikuni 150........same thing applies to all other brand names too.

If you need info on jetting,needles etc i will gladly send all the info i have gathered. also a hell of a lot of confusing info on other forums!
« Last Edit: November 25, 2013, 11:21:06 pm by Woestynhond »
and she said " What are you doin today ? ".
and I said " Nothing ".
and she said " But you did that yesterday ".
and I said "I haven`t finished yet ".
 

Offline bikoholic

Re: Another jetting question
« Reply #11 on: November 26, 2013, 07:32:21 am »
Standard needle? Did you have the DR air / fuel ratio measured? What brand name of jet? Does it lift its front under acceleration in 1st? :ricky:

 Different makes have different ways of measuring their jet sizes so to speak! example: a dynojet 160 will be equivalent to a mikuni 150........same thing applies to all other brand names too.

If you need info on jetting,needles etc i will gladly send all the info i have gathered. also a hell of a lot of confusing info on other forums!

Woestynhond no did not measure the air / fuel ratio, I drilled the mikuni jet with a 1.5mm drill bit = to 150 mikuni main.
1st yes 2nd no, maybe a 43 rear sprocket will help. I will pm you my e-mail address if you don't mind sending me that info.
Who needs a road anyway?