What will my CC's Be??

[proctorbc2005]

I have a tech question, maybe someone here already knows the anwser to, or knows how to figure it out.

Stock 04 YFZ 450 is 439 CC's
A Hot Rods 4.4 storker increases that to 470 CC's (With stock piston)
an CW Big Bore kit will increase to 478 CC'c (with stock crank)

With both components combined it comes out to be 509 CC's, but that is not correct. You have to accout for the extra piston stroke with the 4.4 crank.

So with both components installed what will the final CC count be?

Any gusses?????

[GE4x4]

510.87cc:D

That assuming a 99mm piston with a 66.4mm stroke on a 04.

[MAaudioX10]

Considering CW only builds 98mm cylinders, you actually have 499cc. For some reason, everyone calls it a 501. There must be a couple CC's hiding around in there.

[proctorbc2005]

Thanks for the info guys, I'll call it 500. Seems like a nice round number.:D

[GE4x4]

Originally posted by MAaudioX10
Considering CW only builds 98mm cylinders, you actually have 499cc. For some reason, everyone calls it a 501. There must be a couple CC's hiding around in there.

If it's a 98mm bore and a 66.4 stroke, it's actually a 500.598cc. So a 501 would be close.

[proctorbc2005]

So I guess the stock stroke is 62.0, and 66.4 with the stroker crank, is that how it works?

[MAaudioX10]

Make sure you have that crank balanced. HR stroker crank is not balanced very well and, left unbalanced, will vibrate something horrible. Likely, will cause premature bearing failure.

Another thing you need to be aware about, is if you intend on get or, have, the "oil upgrade" mod. You can not run a X-Forged piston unless it is machined. The additional stroke is added to the bottom of the stroke and, the piston can, and will, contact the squirter.

In addition, 501 setups will require more maintenance. Since the HR crank is a short rod, the rod length changed and, so did the rods "angle of attack". The piston will now be push against the cylinder wall resulting in higher piston skirt wear and, ring wear.

In short, you've been warned.

[proctorbc2005]

How often would this cause a problem? I mean it this going to be a 20 hr and done kind of thing, or it in not that extreme. I ride alot on the weekends, maybe 15-16 hours twice a month. If I am going to have to change rings every other month, I will just not do the mod.

[MAaudioX10]

Originally posted by proctorbc2005
How often would this cause a problem? I mean it this going to be a 20 hr and done kind of thing, or it in not that extreme. I ride alot on the weekends, maybe 15-16 hours twice a month. If I am going to have to change rings every other month, I will just not do the mod.

For what I have been told by, as far as I am concerned, the best guy in the business; John Stallworth. There are many factors but, I was told every 30-40 hr on the rings and, every 60-80 on the pistons.

Now, keep in mind, that is not gospel. Those are simply recommended intervals from one of the best engine builders around. I've ran the HR +3 crank, well to you 4.4, before and had nothing but problems with it. Mine was even balanced. That crank cost me 2 motors. Had to replace the rod bearing twice and, 2 months ago, it threw the rod out of the cases. That was on a 501 setup too.

At that point, I pulled the stroker crank out and, installed a HR heavy duty 06' crank. Got a gen 2 CW 98mm cylinder, Venom 14.25:1 piston and, slapped her back together.

According to my butt dyno, my 478 doesn't quite have the bottom end as the 501 but, mid and top end felt comparable. And, don't have to worry about vibrations or, 300 different clearances.

IMO, forget about the +4.4 crank. Look into a 06' stroke crank, which is 1.4mm more over 04-05's, CW cylinder, CP based piston, Port and Polish, cams, FCI, and a quality exhaust and, you should have yourself quite the screamer while maintaining some reliability. Definitely won't be chewing up pistons as much.

[proctorbc2005]

Originally posted by MAaudioX10


IMO, forget about the +4.4 crank. Look into a 06' stroke crank, which is 1.4mm more over 04-05's, CW cylinder, CP based piston, Port and Polish, cams, FCI, and a quality exhaust and, you should have yourself quite the screamer while maintaining some reliability. Definitely won't be chewing up pistons as much.

So let me get this right. I can put the 3mm (from an 06-08) crank instead of the 4.4 from the 04-05. and it will bolt right up? I have already purchased the stroker 4.4 crank, if necessary, I will ask the company to exchange it for just a heavy duty crank.

Has anyone else had good/bad experiences with the stroker cranks? If so tell me so i can make an informed choice.

Thanks guys.

[MAaudioX10]

Originally posted by proctorbc2005
So let me get this right. I can put the 3mm (from an 06-08) crank instead of the 4.4 from the 04-05. and it will bolt right up? I have already purchased the stroker 4.4 crank, if necessary, I will ask the company to exchange it for just a heavy duty crank.

Has anyone else had good/bad experiences with the stroker cranks? If so tell me so i can make an informed choice.

Thanks guys.

Just to clarify, the +4.4 crank is also known as a +3. 04-05 YFZ have a stroke of 62mm. In 2006, Yamaha increased the stroke to 63.4 to make the bike a true 450cc's.

So, on a 04-05 machine it increases the stroke by 4.4mm and, on an 06-09 machine, it increases the stroke 3mm.

So, when I recommended a 06' crank, the increase in stroke will only be 1.4mm. Used in conjunction with a 98mm cylinder, your displacement will be 478cc.

Check out YFZcentral.com. You'll run into more guys with experience with Hot Rod cranks.

[proctorbc2005]

Ok I understand now the 4.4 and 3 are the same stroke length, just a diffrent number because diffrent sock length. I was not aware they increased the "stock" stroke on the 06 model.

So I need to get my hands on a "stock" stroke 06-08 heavy duty crank. Ill contact the company I purchased the 4.4 from and see if they are willing to do a swap. I may take a hit on the shipping, but if it saves me hundreds in the long run it will be worth it.

Thanks for the info.

[tsargent4]

BEEN THERE, DONE THAT....strokers are not worth the time and money or the hassle being pissed off cuz your quad is fried...go for the '06 style crank and your good...