Tuning a CR500 for higher rpm

Hello.
Anyone here tried to get some more rpm out of the L/C CR500.
When riding on the street the maximum 6500RPM is a bit low.

The cylinder has high duration times so the pipe is the issue.
Is there any aftermarket pipes I can buy?

Kind Regards

my brother had a 1986 500 that had been ported and had an Up-Tite pipe on it
it definitely ran a higher RPM but never really checked the difference except that it would stretch your arms and slide you pants as you slid back on the seat
not sure who ported it but he bought it from a desert racer back in the day
it was fast!!
actually too fast for anything but the open desert

are you running a 40mm carb or a 38
is your timing at 2.2 or retarded to 1.9mm BTDC

i'm running a PWK 39, but didn't notice any difference in the rpm when i changed from the VM40.
I couldn't fit my caliper to measure but the SEM is at 15 degrees at TDC.

the 82 cr500 was max hp at 7k according to the magazine dyno . has a graph etc .intersting that peak torque and hp are within 1000 rpm of each other .
but then i see in the "slavens ported 500" thread someone claims the maths on the porting adds up to max power at 9k

That's my calculations.
My tuner friend told me that the cylinder is tuned like snowmobiles 2-strokes.
They have high port durations and the power is adjusted with the exhaust.

cool . yeah i wasnt trying to imply what u were saying was incorrect or Gospel .
what do the other big bore 2 strokes rev out too ? is it realistic for something as under square as the husky 500 to stay together and/or make good power at 9k ?

No problem =)

It would probably last a race or two.

Honda Cr500 revs 9000 if you want.
But they have 89 bore and shorter stroke.

Anyone here tried the Dynoport pipes?
Is there any other manufacturer who makes pipes to the late 500

different application, but im very happy with the dynoport system on my 360. fits great and is very well made. when i buy a pipe for a swede they would be first choice. the bike pulls better everywhere, which i have heard is their specialty. im sure if you were after higher rpm they would alter a pipe for you upon order. i also run the big core spark arrestor and it has a nice growl and deep tone without being overly loud.

The gnarly on my 360 is better throughout rev range and half the price of dynoport by the time it would have gotten to me, humm big bore 2 stroke i need one cr 500... I want one

most of their mufflers kinda look the same, i think mine is basically their big core barker cut down with the spark arrestor section welded on. all nice dirt bike grade tigwork

have you been able to compare them?
would be nice if pro circuit made pipes for swedes that were still available. dp still has them for all lc huskies up to early 2000s

Hi Nikel!
what about try the easy way? try shorten the header an inch or two
I ran a modified wr400 pipe on my lc500 at first. lost som bottom end and midrange, but sure as hell pulled higher rpm's!
I am now running a stock 500 pipe and has a lot more midrange but I miss the high revs!
with the 400 pipe it would do 150km/t in 5th gear, now with the 500 pipe it only does like 150km/t in 6th... so the rpm is redused for sure!

-Martin

Don't forget the option of a larger front sprocket. With the extra torque and horsepower we can add a larger tooth front sprocket and take back some rpm and add more speed while lowering the rpm.

yes, but I think I am at 15/48 already...

Hi everyone.

I have thought about shortening the stock pipe and I have calculated my own pipes to.
But it's not the easiest jobb to make it fit nice.

I have spoken to Rich at Dynoport and he can custom made a pipe for mid and high revs like he do on the Cr Honda.
$695.
Expensive but I guess it worth it.

Maybe I would see if the 400 pipe is easy to get hold of..

Bigbill I am already running with a 16 front sprocket and a 48 in the rear.
Not much to do there.

Nope i couldnt justify two expansion chambers, i ment the gnarly has more everywhere over the stock specs pipe.

I have emailed a Swedish company about the pipe.
Well see what they say about my ideas.

Have you thought of trying a pipe from a more modern open class bike , that is what I had on the 1962 Greeves MDS I used to race, an early Husky Evo pipe in fact, worked 100%. Much easier to cut and shut than build a new one. You must be very brave to want a Cr500 to go even faster!