Jetting changeds from 07-08 ?


13 replies to this topic
  • mxmaddman

Posted April 02, 2010 - 06:33 PM

#1

I just put my 08 motor in my 07 and everything else besides the motor and electronics is 07 including the carb. I cleaned the carb out while i had it out it was a little dirty.

I started it up and it is very lean.. pops and wont idle down, the headers glowing in a matter of seconds.

SO ... either I missed some dirt or the jetting specs changed from 07-08

Anyone know if the jetting changed?

Thanks!!!!!

  • grayracer513

Posted April 02, 2010 - 07:15 PM

#2

Read:

http://www.thumperta...892#post6980892

http://www.thumperta...897#post6980897

  • mxmaddman

Posted April 03, 2010 - 03:37 PM

#3

Yea, I read them before I posted. So if I gather right they had anything from a 42-48 stock so mine im guessing it has a 42, it even pops on decel with the choke on.. I am pulling it apart in a few days. I'm going to try the "in the bike" jet change you described in your sticky. hopefully it doesn't take as long as just taking the carb out. I have a 48 I am going to try and see what happens.

  • grayracer513

Posted April 03, 2010 - 04:57 PM

#4

If you had read to the bottom of the specific post I linked you to, you would have seen that the '07 came with a 45 stock. Not something like one, a 45. This info is also in the service manual.

  • mxmaddman

Posted April 03, 2010 - 10:47 PM

#5

If you had read to the bottom of the specific post I linked you to, you would have seen that the '07 came with a 45 stock. Not something like one, a 45. This info is also in the service manual.


I see. I read several other post that people claim they had 42 stock & 45 stock..

However, simply stating they both had a 45 would have clarified it from the get go. Those links you sent me are what made me question it to begin with prior to me posting. They are filled with misinformation and or assumptions.

I have the FSM and don't see the year specific info in it anywhere. Since mine was made in 07, Its not going tell me what the 08 had since it wasn't even made yet....

  • grayracer513

Posted April 04, 2010 - 07:24 AM

#6

... stating they both had a 45 would have clarified it from the get go. Those links you sent me are what made me question it to begin with prior to me posting. They are filled with misinformation and or assumptions.

I have the FSM and don't see the year specific info in it anywhere. Since mine was made in 07, Its not going tell me what the 08 had since it wasn't even made yet....

In order to state accurately what the '08 had in it, I would have had to look it up. Rather than do that, I gave you the resource to look it up for yourself.

The links I sent are each to one specific post within a thread. If either of these contain any assumptions or misinformation, I'd like you to point it out for me so I can correct it. Both posts contain the exact info you asked for.

The threads themselves contain info regarding the jetting members are using. Whether it's optimal or not is open to speculation. As I state:

The people who post here are of all skill levels. This information is only intended to let you see what others are using, and cannot be taken to mean that the information is accurate, will apply to your use correctly, or even that the poster's bike runs right with the posted setup. Use it as a guide/starting point only, and look at as many relevant postings as you can before proceeding.



The service manual for the '07 is entirely year model specific. OEM jetting is found on page 2-8.

  • mxmaddman

Posted April 04, 2010 - 08:17 AM

#7

When I click on each link it brings up over 30 posts ranging from 2005-2008.

However, I got the answer to my question.
Thanks for your help.
I will post when I find out more about what the cause was.

Visit the ThumperTalk Store for the lowest prices on motorcycle / ATV parts and accessories - Guaranteed
  • grayracer513

Posted April 04, 2010 - 08:38 AM

#8

The first link should take you directly to post number 28 in the '06-'07 jetting DB.

The second should take you directly to post number 6 in the '08-'09 DB

I always test them when I post them, and they still work.

  • mxmaddman

Posted April 04, 2010 - 09:37 AM

#9

They are working now.

The links you first posted was http://www.thumperta...tml#post6980897
Your revised links are http://www.thumperta...892#post6980892

  • grayracer513

Posted April 04, 2010 - 08:12 PM

#10

The original link that I posted, which still works for me is (in quotes so as to prevent its display from being shortened by the board software):

"http://www.thumpertalk.com/forum/showthread.php?p=6980892#post6980892"

The link you claim I posted is quite different, and leads to nowhere:

"http://www.thumpertalk.com/forum/archive/index.php/t-694918.html#post6980897"

From a technical standpoint, I'm interested in how it got that way.

  • mxmaddman

Posted April 06, 2010 - 05:44 PM

#11

Well I cleaned the jet and blasted out the passage with air and cleaner and found out it has a stock 45 in it. Its running the same still lean and backfiring. The funny part is it still starts first kick every time.

If the 08 ran fine with stock jetting and the 07 ran fine with stock jetting this leads me to believe either somethings different between the carbs or there's some dirt hiding in it.

  • grayracer513

Posted April 06, 2010 - 06:24 PM

#12

Read:

http://www.thumperta...ad.php?t=327405

I do hope you aren't basing your entire theory on whether your bike is lean or not on whether it backfires on decel.

  • mxmaddman

Posted April 06, 2010 - 06:58 PM

#13

Read:

http://www.thumperta...ad.php?t=327405

I do hope you aren't basing your entire theory on whether your bike is lean or not on whether it backfires on decel.


No, Its definitely lean. When i let off the gas from a light blip it shouldn't crackle snap pop and return to idle slow. When the slide shuts it should idle. I'm positive its lean. I tried the idle screw trick already, it made it better backing it out but its still bad. Like I said the header will start to glow almost immediately. Its almost like the hot start is stuck open, but its not and when i let it go you can hear it bottom out in the carb.:thumbsup:

  • mxmaddman

Posted April 08, 2010 - 10:07 PM

#14

No, Its definitely lean. When i let off the gas from a light blip it shouldn't crackle snap pop and return to idle slow. When the slide shuts it should idle. I'm positive its lean. I tried the idle screw trick already, it made it better backing it out but its still bad. Like I said the header will start to glow almost immediately. Its almost like the hot start is stuck open, but its not and when i let it go you can hear it bottom out in the carb.:thumbsup:


well I just got done with cleaning and inspecting the carb.. everything is in order and spot less. air and cleaner flow through all the passages freely and everything looks great. I put it back together with a 48 and still the same thing.

So as i was sitting on it almost ready to put it away for the night I figured I would start it one more time before calling it quits. The problem was gone. idled fine no popping, no red pipe, nothing...:lol:

The only thing i can think of is the hot start o ring is bad. I took it out and checked it and it looks fine, but who knows if its actually sealing correctly. I was flicking it when i was sitting on the bike and that's the only thing that changed between the first few times I started it and now. I will replace it and I am pretty confident that was it all along.





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