Thanks to bannedcr500riders.com
Thanks to bannedcr500riders.com
I would like to start by thanking everyone on this site for their help over the past several months - a special thanks to all who have been patient with my often elementary questions. Yesterday I took my first ride on my Gen 1 CR500 conversion. It turned out to be a very nice bike - I now have to work on the aesthetics a bit with new plastics etc. I will get some more pictures this week and post them. The bike handles very nice and I notice very little vibration over my YZ 250. The bike makes very good power on the bottom end but I did notice the hit is almost non-existent - almost four stroke type power build. My YZ250 seems more aggressive on the top end - more hit so to speak. While increasing the RPMs I was waiting for the "powerband" hit but it never did. I am wondering if the flywheel weight could make this much difference. I am thinking as well of replacing the PJ38 with a new 39.5 PWK - have others who have did this noticed a big difference in power?
Steelie Build Done
Gen 1 CR500 AF Complete - SOLD
Gen 1 CR500 AF Complete - SOLD
-
- Last active:
The fly wheel weight is your problem, these products are designed to give the big bore a tame tractor feel. if you want two stroke hit get rid of the weight. some guys that like the lightswitch feel are running cr250 flywheels....lighter, smaller. come on harder, faster...
I don't see any need for changing your carb. get the bike back to stock. see how it feels, then make adjustments.
I don't see any need for changing your carb. get the bike back to stock. see how it feels, then make adjustments.

Is it running? Yes? It's in the powerband then. 
I ran a flywheel weight for awhile to help prevent stalls at very low speeds.
On a whim, I pulled it off and the bike woke up again.
Yes. It can make that much difference.
Pull the flywheel weight, you'll get most of the hit back and it won't be so lazy up top.
It goes without saying that other things can steal the hit as well. Porting, inadequately sealed exhaust, dented pipe just to name a couple. But you already knew that...

I ran a flywheel weight for awhile to help prevent stalls at very low speeds.
On a whim, I pulled it off and the bike woke up again.
Yes. It can make that much difference.
Pull the flywheel weight, you'll get most of the hit back and it won't be so lazy up top.
It goes without saying that other things can steal the hit as well. Porting, inadequately sealed exhaust, dented pipe just to name a couple. But you already knew that...
No longer have a CR500.
07 Yamaha YZ250, 17 Husqvarna 701 Enduro
Get on with riding or get on with dying.
https://www.youtube.com/mojoscojo
07 Yamaha YZ250, 17 Husqvarna 701 Enduro
Get on with riding or get on with dying.
https://www.youtube.com/mojoscojo
Carbs
So will the 39.5 and 41 PWK fit the stock intake and air box?AlisoBob wrote:Go for the 41mm......
Fat jetting makes any CR500 seem lazy on top.... I would check this first.
The FWW is coming off - I knew it made a difference but I never thought that it would make a huge difference.
I was thinking NO2 activated by the rear brake pedal.

Steelie Build Done
Gen 1 CR500 AF Complete - SOLD
Gen 1 CR500 AF Complete - SOLD
- Roostius_Maximus
- Site Admin
- Posts: 4641
- Joined: November 16th, 2007, 3:24 pm
- Last active:
- Location: Mt Nebo, Manitoba, Canada
- Contact:
the reed side flange is 1mm larger on pwks, but fits
http://www.youtube.com/user/500bigbore
My CR500 Tech Reference... http://sdrv.ms/1a0CIiz
MRE Components... http://sdrv.ms/1bs2zhd

My CR500 Tech Reference... http://sdrv.ms/1a0CIiz
MRE Components... http://sdrv.ms/1bs2zhd

Re: Carbs
I getting tried fighting with my stock PK And thinking about getting a PWK 41 where can I pick one up for a good price and what jets should I ask to have put in it when I order it.
Stock Cr500 Motor, CR250 Ing system complete, P/C AF pipe and FMF Silencer ride in Califonia City CA, 95% of the time I live Here.
So will the 39.5 and 41 PWK fit the stock intake and air box?
[/quote]
Yes, the 38mm PJ, and the 39mm and 41mm PWK all interchange[/quote]
Stock Cr500 Motor, CR250 Ing system complete, P/C AF pipe and FMF Silencer ride in Califonia City CA, 95% of the time I live Here.
So will the 39.5 and 41 PWK fit the stock intake and air box?
[/quote]
Yes, the 38mm PJ, and the 39mm and 41mm PWK all interchange[/quote]
- Roostius_Maximus
- Site Admin
- Posts: 4641
- Joined: November 16th, 2007, 3:24 pm
- Last active:
- Location: Mt Nebo, Manitoba, Canada
- Contact:
k, so now that i have a pwk (from Bob) on my '03 bike, i can say its mildly different for setting up, BUT i have 2 bored PJ's, one on the '88 + one on the '00 that are absolutely excellent carbs but its all based on use. The pwk might be crisper off idle to a frog-hair of throttle, the bored pjs seem to be good all arround but shine for uptop rpm
http://www.youtube.com/user/500bigbore
My CR500 Tech Reference... http://sdrv.ms/1a0CIiz
MRE Components... http://sdrv.ms/1bs2zhd

My CR500 Tech Reference... http://sdrv.ms/1a0CIiz
MRE Components... http://sdrv.ms/1bs2zhd

what did you do your PJ to ?. i took mine out to 40mm and it works really well i believe. i'm running a rad valve and it's wakened the top end up a bit whilst retaining the smooth tractor pull type feel through the lower and midRoostius_Maximus wrote:k, so now that i have a pwk (from Bob) on my '03 bike, i can say its mildly different for setting up, BUT i have 2 bored PJ's, one on the '88 + one on the '00 that are absolutely excellent carbs but its all based on use. The pwk might be crisper off idle to a frog-hair of throttle, the bored pjs seem to be good all arround but shine for uptop rpm
13 isnt unlucky i just keep falling off