HMF Engineering Forums  

Go Back   HMF Engineering Forums > Sport Quads > YFZ450
Register FAQ Members List Calendar Search Today's Posts Mark Forums Read

Reply
 
Thread Tools Display Modes
  #1  
Old 03-06-2012, 03:43 PM
RockinRob RockinRob is offline
Junior Member
 
Join Date: Feb 2012
Posts: 7
Default 2012 YFZ 450 w/carb

Hey HMF guys, alot of us who have bought the new 2012 YFZ 450 with the new BSR 42mm carb are having problems finding any jetting resources for our machines. Can you guys help us out with some slip on, and full exhaust settings. It would be VERY appreciated. Looking at the Comp series slip myself.
Reply With Quote
  #2  
Old 03-07-2012, 08:48 AM
Mike/HMF's Avatar
Mike/HMF Mike/HMF is offline
Tech Nerd Super Tuner
 
Join Date: Oct 2004
Location: Cleveland
Posts: 532
Default

Check it out Rob.

2012: Slip on & Full: No Airbox Lid 165 Main Jet. Move the washer to the bottom of the needle.

2012: Slip on & Full:Air Box Lid On Stock Main Jet. Move the washer to the bottom of the needle.

This is what worked best for us on our test quad. This carb is a bit more forgiving than the FCRs on the earlier models. The throttle response isn't as quick as the FCR, but the "throttle stab bog" is nearly non-existent.
__________________
(866) HMF-PIPE
mike@hmfracing.com
05 TRX450R
Team HMFRacing.com
Keep it between the trees!
Reply With Quote
  #3  
Old 03-08-2012, 10:08 AM
RockinRob RockinRob is offline
Junior Member
 
Join Date: Feb 2012
Posts: 7
Default

Thanks alot for the info Mike. What do you mean by the BSR is more forgiving?
Reply With Quote
  #4  
Old 03-08-2012, 12:47 PM
Mike/HMF's Avatar
Mike/HMF Mike/HMF is offline
Tech Nerd Super Tuner
 
Join Date: Oct 2004
Location: Cleveland
Posts: 532
Default

The FCR carbs are notorious for bogging when you stab the throttle. Your BSR won't cause the engine to bog as much if at all. Also woods riders will probably like this carb better because its not as hard on your arms.
__________________
(866) HMF-PIPE
mike@hmfracing.com
05 TRX450R
Team HMFRacing.com
Keep it between the trees!
Reply With Quote
  #5  
Old 04-07-2012, 12:57 AM
jtwtre jtwtre is offline
Junior Member
 
Join Date: Mar 2012
Posts: 3
Default 2012 yfz450

I jetted the carb on my bike did what hmf sugested droped the washer to the bottom ran so bad!!! after messing with the air fuel screw so much never could get it so i put it back to stock runs way better but now my air fuel screw leaks??? not sure y i pulled out out on aceident put back in leaks now but i have been messing with it to get the poping to stop when letting off the throttle any sugestions
Reply With Quote
  #6  
Old 04-09-2012, 08:46 AM
Mike/HMF's Avatar
Mike/HMF Mike/HMF is offline
Tech Nerd Super Tuner
 
Join Date: Oct 2004
Location: Cleveland
Posts: 532
Default

When you test rode with washer on the bottom did you have the air box lid off? What was the thickness of the washer you moved?

Fuel screw has an O-Ring that may have been torn in the process of removing and installing. Should be able to get a Viton O ring replacement locally.
__________________
(866) HMF-PIPE
mike@hmfracing.com
05 TRX450R
Team HMFRacing.com
Keep it between the trees!
Reply With Quote
  #7  
Old 04-10-2012, 10:07 PM
jtwtre jtwtre is offline
Junior Member
 
Join Date: Mar 2012
Posts: 3
Lightbulb 2012 yfz

Quote:
Originally Posted by Mike/HMF View Post
The FCR carbs are notorious for bogging when you stab the throttle. Your BSR won't cause the engine to bog as much if at all. Also woods riders will probably like this carb better because its not as hard on your arms.
no i moved the thick washer and no i dont think i tore the o ring cause i put it back stock and runs great now? not sure y it was runnig that way.But next time i will just take it in probly cause the new carb is nobody really nows any thing about it there are no forums.
Reply With Quote
  #8  
Old 04-11-2012, 08:35 AM
Mike/HMF's Avatar
Mike/HMF Mike/HMF is offline
Tech Nerd Super Tuner
 
Join Date: Oct 2004
Location: Cleveland
Posts: 532
Default

There should also be a thinner washer. This is the one we moved.
__________________
(866) HMF-PIPE
mike@hmfracing.com
05 TRX450R
Team HMFRacing.com
Keep it between the trees!
Reply With Quote
  #9  
Old 04-16-2012, 10:49 PM
jtwtre jtwtre is offline
Junior Member
 
Join Date: Mar 2012
Posts: 3
Default

Quote:
Originally Posted by Mike/HMF View Post
The FCR carbs are notorious for bogging when you stab the throttle. Your BSR won't cause the engine to bog as much if at all. Also woods riders will probably like this carb better because its not as hard on your arms.
Ok i will have to try to move that one.
Reply With Quote
  #10  
Old 06-26-2012, 12:59 PM
2012yfzfour50 2012yfzfour50 is offline
Junior Member
 
Join Date: Jun 2012
Posts: 4
Default

I too have the 2012 yfz carb model and just purchased the hmf comp series and the basic jet kit w/ the uni filter I live in Florida and its hot and humid 80% of the year what jets can I plan on running when the pipe gets here? Any help would be greatly appreciated
Reply With Quote
Reply


Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off



All times are GMT -4. The time now is 01:38 PM.


Powered by vBulletin® Version 3.6.5
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.