450r expert opinion

[atb7346]

I just bougth a 2006 stock 450r electric start. I have a couple of questions that hopefully someone can answer. Is it just me or is the engine noise really loud. I am not a mechanic, but it sounds like the crank. Are these bikes suppose to make a lot of noise from the crank and cylinder area?

It hesitates a lot at first take off or if you punch the throttle. The guts of the pipe have been removed and if I take off the air box lid, it boggs a lot. Am I just running lean. Should I adjust the slow jet. Does it have a slow jet?

I think the front suspension has lost oil or something because I see no change when I adjust the screws on the reservoir or at the bottom of the shock.

Please give me some advice.

Thanks

[bloodmoney23]

yes the valve train is pretty noisy on these but shouldnt be ungodly. Could be a number of things, valve clearance, cam chain tensioner, rod, crank....im sure it is prolly nothing but if you arent a mechanic you may wanna take it to a show and have them check clearances and do a once over. Any problems with throttle response would be jetting. if you want to take off the air box lid you are going to have to beef up the jets. More air + same amount of fuel = not good. I would up the main jet one size just for the spark arrestor that was taken out. Plus you gotta remember it is alot colder out and it may be jetted for warmer temps. The stock suspension on these arent the greatest and you wont notice much of a difference with adjustments, either buy new ones or send your stocks into C&D or GT Thunder to get revalved and its very much worth it.

[atb7346]

Thanks

I have rebuilt a 400 ex motor before so I have a little experiance. I checked the clearances and they are within tolerances. How much does it genarally cost to get revalved?

[bloodmoney23]

i got a quote from C&D of $700 for all 3 and that was also to adjust them to fit +2.5" a-arms. You would get new springs and internals. Im not sure didnt get a quote from GT Thunder but im sure someone on here will be able to help you out with that. Alot of guys are running the GT Thunder revalves on these forums.

[d3ktrix]

If u took the air box lid off you need a drastic change in jetting.
Running stock jetting with the air box lid off can cause serious engine damage.

Did u buy the bike used with the air box and baffle already out? Meaning theres a chance the old owner jetted it?
Or did u buy it new and remove them ur self w/o changing the jetting?

The bogging u are talking about is from a lean spot in ur jetting.

[atb7346]

I bought it used with the air box lid on and the pipe gutted. It is hesitating with the air box lid on and obviously even worse with the air box lid off. I am eventually going to run with it off.

you def. have jetting issues, but the off idle bog is not caused by the main, pilot, or needle jet. however, those may make it worse...

a smaller leak jet will solve that...try going to a 55 from a stock 70...

[d3ktrix]

Originally posted by speedyquad

a smaller leak jet will solve that...try going to a 55 from a stock 70...

BTW, the smaller the # for the leak jets, the larger the hole in the jet (More fuel)
Opposite of the other jets.
Your right tho recommending the #55.

atb7346, for a 06 with the airbox lid off I'd recommend HRC jetting.

The following should be a good starting point for you. Might have to fine tune some.

165MJ (160-170 range)
HRC Needle
45 pilot
#55 Leak Jet

If you prefer not to have to change so many jets, you can leave the air box lid on and just switch the leak jet to a #55.
This should be enough to fix the lean bog if the lid is left.