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Discussion Starter · #1 ·
'08 T100... So far I’ve removed the air injection, snorkel with out bellmouth (I just pulled the snorkel out of it’s housing and replaced the housing to keep the stock filter in place), replaced my stock pipes with BC Predators and jetted the carbs to 135/main and 42/pilot with air mixture turned out 2.5 turns per British Customs recommendation. However, I’m still getting popping on deceleration and from what I’ve read so far here, this would indicate that I’m running a little rich (too much fuel). I’ve heard that a little popping isn’t bad, but I don’t know how much as too much. Any chance that just simply turning the air mixture screws out a tad to allow more air could remedy this? I’m hoping this could remedy the problem as I really don’t feel like digging into the carbs again. I have yet to figure out how to get the pilot jets out with out having to remove the boots.
Any help would be appreciated.

Regards,
Chris
 

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I am no expert but I have no airbox and open cans on my bike are run 128/42's and have no popping. I am not saying that i am right but that is what I have.
 

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As far as the mixture screws go, I found the following method to work real well:
- Warm up the bike completely
- While idling, give it a rev
- if it drops, then hangs for a second at a higher RPM, you are too lean. Open up the screw a quarter turn and try it again.
- if it drops below idle, then bounces back up to idle, you're too rich. Close the mixture screw a quarter turn.

This procedure is documented in the Jenks Bolts tuning guide and worked well for me.
 

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Interesting Pokey. I am going to try that on my bike. Right now I am 2.5 turns out on mine with no popping but haven't tried the rev test.
 

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Discussion Starter · #5 ·
Is it posable to get popping on deceleration if you're running too lean?
 

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popping on deceleration is a lean condition NOT a rich condition
 

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+1, you are running LEAN, not rich. Bump your mixture screws out a little. You may need to take em out to 3 full turns. Check the Jenks info. On their advice, I drilled out the little holes in the slides to 3.0mm when I did the airbox chop and rejet. No popping.

Does it run well otherwise? Any flat spots in acceleration? How does it start when the engine is warm (no choke)? A bit more info would help in proper diagnosis.

FWIW, I kinda miss that snap/pop routine when I decell, but not enough to rejet or lose a good setup...
 

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Turn the idle mixture screws out until the popping stops or the screws fall out. If the popping stops...great. If the screws fall out, get #42 pilots and start over...
 

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Discussion Starter · #9 ·
Thank you everyone for your reply's. It's been very helpful and insightful. I took the air mixture and turned them in 1/4 turn. Popping got worse. I then turned them out 3 full turns from fully closed and the popping is still there... barely, but much better. I think another 1/8 to 1/4 turn and I may be there. It's suppose to snow tomorrow here in the Emerald City so I'm not sure how much riding I'll get done tomorrow.

Thanks again guys. Your help is greatly appreciated.

Cheers,
Chris
 

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'08 T100... So far I’ve removed the air injection, snorkel with out bellmouth (I just pulled the snorkel out of it’s housing and replaced the housing to keep the stock filter in place), replaced my stock pipes with BC Predators and jetted the carbs to 135/main and 42/pilot with air mixture turned out 2.5 turns
Bluesforchallah,
If the above is all that has been done to your airbox/intake then you may want to reconsider the size of main jets you're running.

Regardless of popping problems, which may in fact just be a product of the pipes you have and not a mixture issue, to run 135's with only minimal intake freeing up would suggest your running VERY rich at everything over about 3500 rpm.

How does your bike run?

You may get some guidance on jets sizing here..........

http://www.triumphrat.net/1128200-post6.html

My suggestion on correct idle screw setting is to keep turning out the screws (enrichening) until the idle revs begin to falter.
From this position turn them back in 1/2 turn.
You wont be far wrong from there


V.
 

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I have TORS on my Scrambler and it pops and bangs like a good un. The AI is still in place but I quite like the popping and banging. Should I be richening the mixture up a bit or will it be ok as it is if I'm ok with the noises and the way it's running?
 

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I know this is an older post and did what I was supposed to do. Used the search function:). I have a similiar set up but with a polaris bellmouth. I was running into the same problems. I had to shim the needle .30th because of a lean surge between 3000 - 3500. My pilot screws are at 3 out now with a little popping on deceleration. I will probably turn them out to 3 1/4 and give that a try.
 

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and can..

can the wrong mix screw anything up otherwise/enginewise? I kinda like the popping too-but have followed this thread and then starting wondering if being lean (popping on decel) can screw anyhting up?
 

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The truth is, a perfectly stoichiometric tuning job will probably pop a little on decel. To eliminate it, you just about have to tune the idle mixture a little on the rich side. Excessively lean tuning will be indicated by white or burned plugs, pinging, and other symptoms of really hot combustion chambers.
 
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