Or view bikes by:
 - new additions
 - brand
 - year
 - category
 - 50cc or 125cc
 - top charts
New 2014 models New
All 2013 models
MC of the year
News and reviews
Discussions
Words and terms
Unit converters
Riding safety
Home

Free classifieds

Submit motorcycles
Advertise products
Contact Bikez
About Bikez
Privacy Policy
Biker personals




carb modification - outside the box options 81 Yamaha XJ 650 discussion forum:
carb modification - outside the box options

carb modification - outside the box options 
Dan said 2011-05-13 04:10:10 
 
So I have been chopping up and customizing my ’81 Yamaha xj650 maxim. The giant air box is gone and I have replaced it with four individual carb air filters that mount directly onto the carburetor. However, as mentioned in a previous post, there is a lot of spitting and sputtering and backfiring which used to send fuel back into the old air box/filter. Now that the air filters are exposed, I don’t really want them filling up with fuel and starting a fire between my legs.
So my questions end up being
1) Is all the leakage just a filthy carb?
2) Because of the change in air flow going through the carbs (a lot more air at, possibly, a slower rate), must I replace the jets?
3) If so, do I go bigger or smaller than stock?
4) I have an idea to restrict airflow through the filters by creating metal sleeves that would speed up the air as it is forced through a smaller hole (make sense?) would that allow me to avoid re-jetting?
5) What does back-pressure have to do with back-firing (if anything)? I have stock exhaust on it now, but the baffles were “removed” last time it was put on its side

That seems like a lot, but I would appreciate any direction anyone could give.
Thanks
Dan
 
 
Answer this message                           Show discussion overview

Comments, questions and answersEnter a comment or answer to this message

We invite you to introduce yourself by a few sentences if you are new to this discussion group. Enter your e-mail to join the forum and get notifcations of new messages. Or post your question, answer or comment as a guest. We have just improved this discussion forum and expect the number of users to increase.
 
Title
 
Signature
Optional e-mail
Enter your e-mail to join the forum and get notification of answers and new messages. You can unsubscribe by a single click. Bikez does not show, sell or misuse e-mail addresses.
Message text


More 1981 Yamaha XJ 650 information

Our discussion groups are intended for short messages. We also welcome more extensive motorcycle reviews.

Bikez also recommends that you check out the technical data and the riders' rating for the 81 Yamaha XJ 650. You can also rate it yourself. Use our efficient motorcycle classifieds to sell or buy this bike. Your motorbike gets a high quality presentation. Ads are free.
    Aprilia     Benelli     BMW     Ducati     Harley-Davidson     Honda     Kawasaki     KTM     Moto Guzzi     Suzuki     Triumph     Ural     Yamaha   

Copyright © 1999-2013 by Bikez.com
Motorcycle catalogue and Motorcycle classifieds