Keihin special version - jetting Problems

Hello all,

first I must say I have looked in the Doc and many threads, and have found too many different solutions.....

The bike is a 2001 FE 501.
Starts last year very good with kick and E-Start with the Dello Carb.

Now I have bought a Keihin FCR MX which was original in a Yamaha YFZ450 Quad

I have dismounted the TPS.
Installed a new needle OBDVR (husa manual 2004)
a 45 pilot jet instead of the 42
178 MJ instead of 158.
Pilot air jet 100
And close the "octopus" bypass.

First problem was a bad throttle response.
The second a bad idle, with a too high engine speed for a few seconds.
I think a too lean mix.

The engine has a big bog and stops sometimes.

Now I had found the Tumpertalk forum and have done the modifications:
Dismounting the 0,50 leak jet and displace with a 4 mm screw
(The total quantity of the accel. pump squirts now)
Do the "BK mod" with the M4 srew to limit the lift of the accel. pump, to limit squirt duration

After this the bog looks much better.

But when I to take a example drive 4. Gear with constant speed an less throttle and go fast to full throttle, its a little dropout (bog) and then the engine sprinted very fast away.

So I think its too much fuel without the leak jet.

HAS A ORIGINAL FCR MX CARB A LEAK JET AND WHAT IS THE SIZE?

Whats about the idle?
I have the Pilot mixture screw 3 turns out. Normally for a Yamaha carb?

Pleas note I´m from munich germany, also not in the higher mountains.


Here the links:
http://216.37.204.203/Yamaha_OEM/Yamaha ... A=290&B=10
Yamaha ATV, year 2004, YFZ 450, carburretor

http://www.thumpertalk.com/forum/archiv ... 19805.html

Please help me!

Maybe the right tip is anywhere in this or the tumpertalk forum - please give me the link.


regards, husa98

Hi Husa98,
The following may help.
Jetting

In addition review the Husaberg fuel section as much information is to be had.

Hope this helps.

Sincerely,
Dale

I want you to infirm about the experiment

I go back to the original needle and the original leak jet.
And it works so far - no bog!

It´s also not realy possible to mix different systems - with or without leak jet.
I think the reason is a different diaphragm:
More fuel diaphragm and leak jet (Yamaha..)
Less fuel diaphragm and no leak jet (KTM, Husaberg)

No I have the 45 pilot jet in.
And the engine starts hot not with the e-starter
(Remember: starts fine with the dellorto)
and not really good with kickstarter.

(First I will try the 42 pilot)

Now I think to change the diaphragm and make a complete husaberg jetting .

Wich jetting can you recommended?
Is the original in the owner manual 04 ok?

regards,

husa98

Husa98 said:

Hello all,

I have dismounted the TPS.
Installed a new needle OBDVR (husa manual 2004)
a 45 pilot jet instead of the 42
178 MJ instead of 158.
Pilot air jet 100
And close the "octopus" bypass.

regards, husa98

Click to expand...

put the 158 back in. put the 42 back in, needle clip 4. set the bike on the PS when warm for the best acceleration and you'll be fine!

regards

Taffy