Mountainmax 700 fouling

[hasnick]

I have a 98 MM700. I bought it last year from a guy who liked to mess with the carbs. The elevation in our area is around 1400ft. When I trail ride I can run about 100 miles and the plugs will start to foul. The center carb and the clutch side carb are the ones that give me problems. The exhaust side always runs good and has a good burn on it. I want to drop the needles to lean it out a little. I bought a repair manual from Clymer, but it doesn't go into detail on how to do it. Can it be done with the carbs in the sled? how far should I drop them? How do you get them out? Any help would be greatly appreciated. Thanks.

 

[Turk]

If the sled is not piped run 142.5 mains straight across & drop needles 1/2 right across too.

 

[hasnick]

It is piped. It has a 142.5 in the center and clutch side, and a 143.8 on the exhaust side. I don't know why they are different, it's just what he had in there.

 

[hasnick]

Anyone else?

 

[FuzzButt]

I don't know why they are different, it's just what he had in there.

The novice engineer in me thinks that in the triple there must be enough thermal variation between the Mag cylinder and the PTO cylinder to warrant needing more fuel in the PTO cylinder. For instance 1-145, 2/3-143.8 is your stock jetting which is the same as the SX but different from the srx the other 2 700cc motors from '98.

I'd try Turk's idea but only one thing at a time. Needle or jet. You might only need a minor adjustment. Plugs are cheap.

My 2 cents

 

[hasnick]

I think the jetting is right. When i run wide open for the majority of the trip, I have no problems. It's when I go into a more comfortable trail ride where the problem lies. I know I have to drop my needles. I just don't know how. It looks like I have to take the carbs off of the sled and seperate them to get the shaft that goes through all 3 carbs out. Then I can get the throttle assembly out. i was hoping to ruin into someone that could tell me an easier way. i don't want to seperate the carbs.

 

[srx_eh]

Needle jet removal,

-Remove the top cover off each carb
-Using an allen key remove two screws from the throttle lever assembly
-Clamp down the throttle lever (this will bring the lever assembly to the top so you can get at the needle jet)
-Move the slider up enough so you can pull the needle out of the throttle valve assembly (on my vmax I removed my airbox to allow me to move the slider).

 

[hasnick]

Thanks. I was thinking I could do it that way, but it didn't look like the slides would clear the throttle shaft. I'll try it this weekend.

 

[hasnick]

Thanks for the help. I tried it and it worked. I was under the impression that the whole assembly had to come out. I didn't realize that just the top part comes off and exposes the needle. It only took me 20 minutes. Again thanks for the help.