BannedCR500Riders.com

ok, i would LOVE to get my 95 cylinder 'professionally ported', but i just dont have the $$$...i mean, trying to keep all 3 bikes (85 and 95 cr500's, and a 91 kx500) running, plus the vette, plus the v8 vega, plus the tow business, plus feeding 2 kids...ahhhh, you guys all know the drill, i bet lots of you are just like me--beating sh*t between 2 rocks to make it work ! so i am going to attempt (shudder/gag) to port my own cylinder--i think i read somewheres to raise the exhaust ports 4mm and the intakes 2mm...anyone got any advice for the newguy ? i dont want to destroy my only cylinder, if its a loaded grenade maybe i will just leave it alone. whacha guys think ? thanks....

ive heard the only thing you can do without risking screwing it up is to enlarge the "boost ports"
after looking at my cylinder that roosty did im glad i didnt try to DIY it, theres angles port heights...... theres no way youd be lucky enough to get it right first try
quite a few people believe that raising the peak power isnt really worth it, harder to ride, less reliable.......
i wanted the cr85 powerband on my 500, im glad i didnt do it

im not really looking for the cr85 powerband--what the bike has now on the bottom and mid is fine, i just want more shriek up top . (it now has a twinair filter, 41mm carb, v-force 3,procircuit pipe,fmf "Q" silencer,14-49 sprockets,roostboost ignition coil)...it seems to 'run out of breath' rather quickly ( although it is a LOT better than stock with whats on it now ) and is just begging for another 1000 or so rpm to really crank out the horses...i know, i know, you cant have your cake and eat it too, right ? : bling :...

You obviously have gained enough skill to outride a stock CR500?
I haven't. My ST bike has stock porting with a Roosty head/decomp and it still scares the shit out of me.

what tools you got to work with ?

Check into Flotek performance. http://flotekperformance.com/.

Never heard anything bad from his customers, and he's had a LOT. Well known guy in the 2-stroke community. I've had a cylinder ported by him, and would again.

Check out his site. And his prices are very agreeable too.

Leave it alone...my .02

Rhino89523 wrote:Leave it alone...my .02

I definitely wouldnt do it myself unless it was a spare cylinder. to hack up your only cylinder without knowing what you are doing....well.

we dont know his engine background or what tools he has. need more info. sheeet nikka you guys think im a pro in black magic porting or somethin ? pretty sure mine was atleast good as glens . ok maybe it aint that good but its better than stock

bob maybe all that complaining you did about the stuck piston didnt go on deaf ears. says theres new specs for the trail port . and roostious got new competition. website claims best porting you can get anywhere in the world

read on mofos. this aint no bullshit http://www.gssraceporting.bravehost.com/

poor?????
That conjures up images of West Virginia, Appalachia.

You may be broke, that's different.


Poor is a state of mind.
Broke is a temporary condition.

dude, im so poor i cant even pay attention half the time....hah hah. as for the rest of the comments, lets see--no, i cant outride a cr500--i am not jeremy mcgrath, though i try my best to be.( i was good enough as a kid to be sponsored by a local shop for 4 years, and gave them 3 county championships--till i got to be over 6ft and 250lbs + and started breaking the bikes everytime i rode them....) i just like having way more power than i need-the unexpected wheelies keep you on your toes! as for tools, just the 'norm' like most of you probably do--dremel, drill, carbide bits,etc...as i said, i was just looking for a little more shriek up top. maybe i will just be happy with what i got...

your effort will be better spent on jetting, silencer repacking and reeds, and a clean air filter
fresh silencer packing adds quite a bit to the overrev on a 500..... weird cause on a 80/ 125/ 250 its adds lots on the bottom

2strokeforever wrote:your effort will be better spent on jetting, silencer repacking and reeds...

and boingers....

I spent a rediculous amount of time researching porting a cr500 and had very long detailed conversasions with experts on the tipic and utililzed photos of the well known porting work and when I was finished I wished I hadn't touched it. The powerjet Mikuni 41mm TM and more importantly cr250 CDI gave me far more gains than the porting work. If you are dead set, don't mess with the port timing, open up the intake boost ports until your thumb will fit through (quote from DeWayne) and widen the exhaust doing those 2 make a good increase without turning it into a jetting nightmare. Me personally if I got another cr500 would leave it BONE STOCK with the exception of a PWK and just ride the piss out of it.
My old gen-1 was a really fast bike (when it got traction or I stayed on it) and I would spend an entire day trying to get my jetting right just to get spanked by a 450 that could actually get tracton.

roostys porting is great, but not cheap

d.graves---thank you--thats exactly what i was looking for--someone who tried it and figured out the mistakes so i dont have to make it. thanks again, i already got the 41pwk so i guess the cr250cdi is next...any mods to put it in, or is it a drop in ? thanks again !

danny what year 250 cdi were you running?
the 1999 is pretty mellow

You might want to look into a program to build your own pipe you can build some pretty radical stuff with them but the you'll have a down pipe I think they have some in frame deals but I would think alot more complicated and difficult to build and get right

I know this is talking street bikes but it'll get you in the right direction for getting that extra 1000rpm too http://www.froggy.se/skalmanmc/rd350/tuning/expan1.htm

sounds like you already you knew you couldnt do your own porting but you wanted to hear 10 people say it also just to confirm what you already knew


chumly you think we can just make a pipe on the kitchen table ?????

100hp--no, i didnt know whether i could do my own porting CORRECTLY....and i wanted to see what the general thoughts along those lines were.

im not sure there is a correct way to do it. ask 10 professionals and you likely get several different answers what works best.

It's not hard if you make your measurements perfect then it's just welding

ChumlyRocksa540 wrote:It's not hard if you make your measurements perfect then it's just welding

shit that easy