my new used 426f

[STL450rider]

Got this beast the other day for 400$. Its a 2001 426f I was told the "cams were shot". Pulled the valve cover to find out the previous owner didnt have it timed right, so i took care of that and about 10 kicks later it started ?

The bike sat for couple years so the clutch was frozen together. pulled the plates out and soaked them in oil overnight, put it back together and fixed that. Changed all the fluids and now its good to go, kind of. I think something may be up with the CDI, it will rev up pretty high but no rev limiter kicks in

any suggestions?

[RiderX]

Nice find.

[Bazzaboy7]

I think something may be up with the CDI, it will rev up pretty high but no rev limiter kicks in ?

any suggestions?

What a bargain ... why can't I ever find them

As far aws the rev limiter issue - I would just rely on the rev limiter on the end of your right arm

Enjoy your bargain basement beast

[2grimjim]

I think something may be up with the CDI, it will rev up pretty high but no rev limiter kicks in

any suggestions?

Rev-limit doesn't take effect 'till somewhere north of 11,500 rpm. That's a long ways up thar.

[zlathim]

That's a great score for $400! Congrats on the deal, and for having the know how to get it going again for free.

[grayracer513]

You can hit the rev limiter in low gear pretty easy, but as said, it's set at 11,500, and the power falls off pretty hard at around 10,500, so it's not as easy to do by mistake in the higher gears as it is on a 250F.

[STL450rider]

It feels like it wont rev up high enough to hit the limiter then? Ive owned a few 450s so Im very familiar with what it feels like. I can pull the clutch in and rev the piss out of this thing and it almost feels like it just "stops revving" at about 10ish, like a dead spot, kind of hard to explain. It is jetted very rich on the main jet though (172). I dont know if this could have something to do with it? As far as I know the bike is all stock with the air box lid removed. Seems to have a ton of compression though. I had a yz450 with 13.5:1 piston and this feels pretty close to it when kicking..

[2grimjim]

It feels like it wont rev up high enough to hit the limiter then? Ive owned a few 450s so Im very familiar with what it feels like. I can pull the clutch in and rev the piss out of this thing and it almost feels like it just "stops revving" at about 10ish, like a dead spot, kind of hard to explain. It is jetted very rich on the main jet though (172). I dont know if this could have something to do with it? As far as I know the bike is all stock with the air box lid removed. Seems to have a ton of compression though. I had a yz450 with 13.5:1 piston and this feels pretty close to it when kicking..

The cam chain might be streched enough to need replacing.

As the cam chain wears, it retards camshaft timing. Retard the valve timing enough and the bike won't rev.

Old Toyotas with the 18R/20R/22R engine were famous for this.

[STL450rider]

that would make perfect sense 2grim... can i replace the chain by just puling the cams and dropping the chain down to the flywheel? its been a minute since ive done it

[2grimjim]

that would make perfect sense 2grim... can i replace the chain by just puling the cams and dropping the chain down to the flywheel? its been a minute since ive done it

Yup, you'll have to pull the flywheel, cam chain tensioner, and loosten the chain buffer too. Not very difficult. Probably not a bad idea to replace the cam chain adjuster too, they aren't very expensive either.

[STL450rider]

hmm.. not familiar with the "chain buffer" or cam chain "adjuster" youre talking about?

[Hans Schmid]

For $400 bucks, you did good!

[Hans Schmid]

hmm.. not familiar with the "chain buffer" or cam chain "adjuster" youre talking about?

Its down by the head pipe, close to the exhaust bearings!

[grayracer513]

Download a manual here:

http://www.yamaha-motor.eu/eu/services/owner-manuals/index.aspx

http://www.yamahaownershandbook.com.au/?r=0

Then read:

https://www.thumpertalk.com/forum/showthread.php?p=3150405#post3150405

[STL450rider]

thanks for the manual gray. and thanks for attempting to waste my time other ppl. lol- exhaust bearing

[2grimjim]

hmm.. not familiar with the "chain buffer" or cam chain "adjuster" youre talking about?

There is two chain buffers. They are the black plastic sliders that keep the chain from tearing up the inside of the engine. The front buffer drops in the chain well of the cylinder before the head is bolted on, and the rear buffer has a pivot with two bolts behind the flywheel. The cam chain adjuster is the spring loaded hoolie with two small bolts on the back of the cyclinder (also called tensioner).

[STL450rider]

ahh ok, so chain guides and chain tensioner.. it all makes sense now