RZ/RD 350 & Misc. 2-Stroke Tech BBS

Depends on your definition of "unbearable".
And a properly balanced crank can take away the shakes.

Re-pack your silencers too.

I would just to find a manufacturer who makes size 15 MX boots. My old ones are starting to deteriorate, and Id like something better quality than the ones Ive got. (They were a gft and are from Moose racing)

-Z

Just goes to show- you can hot-rod anything!

You distract the guards while I load these into the van...

Mildly built 421 will have just a bit more grunt. Be reliable too.

Just keep your weight over the front Questo- even in stock form, they hit pretty hard for a big bike when it gets on the pipe! You are gonna have an evil ride.. I would consider balancing & head mod absolutely mandatory though. Or a constant diet of Sunoco silver (100 octane). I decided I'm goin...

Do you have the 4 or 5 speed?
The head mod and porting really wakes the 490 up..
Instead of the old IT frame, I'd love to get it in the WR500 chassis. Superior in every way, except the engine.
And bulbus gas tank.

I know. My Yamaprilia is going to run a little north of $17k when all is said and done. Just thinking about pricing of the IT/YZ later on If I decide to sell it. Ive seen nice (restored) examples going for almost $4k. Getting harder to find parts for it though (its a '83).

What was your turnaround time?
I'm gonna have a $800 crank in a $300 bike..

My '96 CR500 hardly shakes. Its more of a buzz, and except for the silencer, stock. Maybe I just got a good one?

Why does it need to be welded? Are they prone to coming apart? Creates an added layer of complexity when balancing and trueing. Durability. The 490 engine (with proper porting and head mod to run properly) likes to rev. Problem is, like I said before, its so out-of-balance, it shakes like a paint m...

If you do have some extra bucks, titanium fasteners can shed some weight, but the $$ add up quick.
You can also skeletonize or hollow out some parts here and there.

I need a crank trued, balanced to perfection and welded for a dirtbike (IT/YZ490) build. I know the 490 is a paintmixer to begin with, but who can make it the least shakey with decent turnaround time?

Id be satisfied if it only buzzed like my CR500.

alex2218 wrote:These are cast vertex pistons, it seems they dont need the same clearance as Wiseco forged pistons designed for this engine...

This is why I always run forged Wisecos.
Cast pistons are "softer" and more prone to failure.
Get the proper forged pistons and enjoy your new engine!

[/quote]Some people do. But in my opinion they are overkill for a 40-50-ish horsepower bike.[/quote]

I think they add a degree of safety for highly stressed applications and longevity for less stressed engines. Overkill for a 40-50hp bike? Not for a MX 125 turning 13,500rpm!