Got My 450 Head and carb Back from James (JBS)!

Here's a few photos..

cant wait to see it run...soon as its together i will send you my air/fuel gauge!

WV Hot Rod Rhino wrote:

cant wait to see it run...soon as its together i will send you my air/fuel gauge!

Don't worry about sending the gauge just yet brother it maybe a few weeks before I do any tuning.


Got out yesterday and found my valve spring compressor would not work (I knew it would be close if it did) so I didn't get to assemble the head. I did pull the carb apart and clean it up once it was cleaned up good I took my dyno jet needle out of my old carb, cleaned it good, and installed it in the modified carb. I found a 122.5 jet in the 07 carb with didn't seem right because stock my 08 had a 133.5, I went a head and placed a 134 main in the modified carb to give me a starting point. I drilled and removed the plug that enclosed the mixture screw and found the mixture screw to be set about 1/8 a turn out if that, it was basically closed. I took it for a test run and off the line it seems to have a slight hesitation but then it opens up and feels like it excellerates a better, seems to top out faster. I got to do some tuning on the carb to get it dialed in before I can say how much it helped.

It maybe a few days before I can do any more tuning, after changing the carb, shiming the clutch, and changing the weights I decided to give it a hill climb test, I hit a little hill I had hit a couple hundred times and about half way up I heard a pop and the bike shot to the left.. Broke the left rear axle, locked it in diff lock and think I about stripped something in the front diff it popped a few times and the driver side wheel would stop pulling. So I pulled out the winch and winched about 250ft up the steep hill, the contactor was getting hot by the time I hit the top and sometimes it would take a couple hits of the button to get it to engage but it still worked. This is the first time I have been in a position like this but this is the reason I run a winch, it was a life saver.

Installed the carb a while back because I wanted to try it before the head change and it is doing great... I got out today and assembled the head with a webcam high torque cam, springs, and titanium retainers.. waiting on a few more gaskets then I can swap heads and hammer down

Got a couple boxes this evening .... hopefully your gaskets are in there.

WV Hot Rod Rhino wrote:

Got a couple boxes this evening .... hopefully your gaskets are in there.

Got out today and installed the ported head along with a webcams torque cam... Runs a LOT better so far but I got a lot of tuning to do to get it right...