HRC spec powervalve spacer

Vintagehonda.nl
Edited Date/Time 1/4/2021 9:55am
Just made a batch of 15mm (0.59”) powervalve spacers for the 92-01 Honda CR250R. These improve low-end torque and smoothen out the powerband. Purchase here


4
1
|
sandman768
Profile picture for user sandman768
Posts
8164
Joined
3/21/2014
Location
Saratoga Springs, NY, USA
sandman768 12/13/2020 6:17am
12/13/2020 6:17am
Nice... price includes shipping to USA?
Rider 5280
Profile picture for user Rider 5280
Posts
2397
Joined
11/9/2011
Location
Denver Metro, CO, USA
Rider 5280 12/13/2020 8:13am
12/13/2020 8:13am Edited Date/Time 12/13/2020 8:14am
These work AMAZING.

I was very surprised what a simple spacer like this could do.

The Shop

See All »
Tallkid634
Profile picture for user Tallkid634
Posts
28
Joined
3/23/2019
Location
Conifer, CO, USA
Tallkid634 1/3/2021 6:11pm
1/3/2021 6:11pm
I may sound dumb here, but this appears to only space the cover further away from the cylinder. How would this alter the power in any way? Thanks
mxracer666
Profile picture for user mxracer666
Posts
781
Joined
10/28/2010
Location
NE Iowa, IA, USA
mxracer666 1/3/2021 6:42pm
1/3/2021 6:42pm
Tallkid634 wrote:
I may sound dumb here, but this appears to only space the cover further away from the cylinder. How would this alter the power in any...
I may sound dumb here, but this appears to only space the cover further away from the cylinder. How would this alter the power in any way? Thanks
you do...
omalley
Profile picture for user omalley
Posts
1528
Joined
7/27/2016
Location
Snohomish, WA, USA
omalley 1/3/2021 7:25pm
1/3/2021 7:25pm
Tallkid634 wrote:
I may sound dumb here, but this appears to only space the cover further away from the cylinder. How would this alter the power in any...
I may sound dumb here, but this appears to only space the cover further away from the cylinder. How would this alter the power in any way? Thanks
It’s been forever since my last 92-01 CR250R ownership...that said, as I recall, it tricks the engine into thinking it has more pipe volume than it does.

1
Tallkid634
Profile picture for user Tallkid634
Posts
28
Joined
3/23/2019
Location
Conifer, CO, USA
Tallkid634 1/4/2021 8:44am
1/4/2021 8:44am
Tallkid634 wrote:
I may sound dumb here, but this appears to only space the cover further away from the cylinder. How would this alter the power in any...
I may sound dumb here, but this appears to only space the cover further away from the cylinder. How would this alter the power in any way? Thanks
omalley wrote:
It’s been forever since my last 92-01 CR250R ownership...that said, as I recall, it tricks the engine into thinking it has more pipe volume than it...
It’s been forever since my last 92-01 CR250R ownership...that said, as I recall, it tricks the engine into thinking it has more pipe volume than it does.

Didn’t know that cover did anything besides protect parts, linkage, etc. from the elements, didn’t know there was any pressure in there. Likewise been a while since my 01’. Thanks
1
omalley
Profile picture for user omalley
Posts
1528
Joined
7/27/2016
Location
Snohomish, WA, USA
omalley 1/4/2021 9:55am
1/4/2021 9:55am
Tallkid634 wrote:
I may sound dumb here, but this appears to only space the cover further away from the cylinder. How would this alter the power in any...
I may sound dumb here, but this appears to only space the cover further away from the cylinder. How would this alter the power in any way? Thanks
omalley wrote:
It’s been forever since my last 92-01 CR250R ownership...that said, as I recall, it tricks the engine into thinking it has more pipe volume than it...
It’s been forever since my last 92-01 CR250R ownership...that said, as I recall, it tricks the engine into thinking it has more pipe volume than it does.

Tallkid634 wrote:
Didn’t know that cover did anything besides protect parts, linkage, etc. from the elements, didn’t know there was any pressure in there. Likewise been a while...
Didn’t know that cover did anything besides protect parts, linkage, etc. from the elements, didn’t know there was any pressure in there. Likewise been a while since my 01’. Thanks
No worries. I’m going to have to dust the brain off really good on this one, but I believe that part of the function is that the chamber only has access to exhaust gases in a certain phase of PV movement and/or at one end of the RPM range. Thus giving the engine the impression of variable exhaust volume. I could be totally off on this part though. My last CR250 of this engine generation was a 97. I’m not going to do the math as it’ll remind me how old I am, lol.
sdhuskyrider
Profile picture for user sdhuskyrider
Posts
357
Joined
10/27/2017
Location
San Diego, CA, USA
sdhuskyrider 1/22/2021 9:40pm
1/22/2021 9:40pm
That generation of engine used both a variable exhaust port and sub chamber to alter power. The cover is part of the sub chamber.
2

Post a reply to: HRC spec powervalve spacer