1986 Honda CR 250 Power Port

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2/13/2018 10:00 AM

Hi i have a factory manual but it would help if there was a video or better explanation in regards of how to clean and install the exhaust valves in the 1986 Honda CR 250 . There are videos on you tube that show the later versions but not a detailed version for the older CR s.

Thanks Brian

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2/14/2018 9:58 AM

BM wrote:

Hi i have a factory manual but it would help if there was a video or better explanation in regards of how to clean and install the exhaust valves in the 1986 Honda CR 250 . There are videos on you tube that show the later versions but not a detailed version for the older CR s.

Thanks Brian

They are a complicated valve system for sure. I had an 88' back in the day. They are similar to the 86' maybe slightly less complicated. I have been restoring an 88' to relive my glory days with the bike of my youth. When I rebuilt the engine it took me a while to wrap my head around the valves and setup once again even though I am a mechanic for a living and had one that I worked on 20+ years before. I am familiar with them again now. I have my engine in the bike but I am going to put another engine together. I think I will do a video tutorial on the valves with my second engine. I have had lots of help with youtube video tutorials over the years. I have the knowledge and teaching skills to make some videos myself and feel like I should do some to put back to the universe. It is great people take the time to do these videos. A video on cleaning and setting up these valves would help plenty of people struggling with them. Sorry for the long winded answer. I don't know of a video for the 86'/87' valves. What I can say is I had several manuals to look at for info on the valve assembly and setup. Most of the info was either vague or confusing. I found the best info was actually the owners manual. See if you can find a PDF of the 86' or 87' owners manual. My 88' owners manual had by far the simplest explanation of it all. Here is the 88' info. I know it is a bit different but maybe it helps. For cleaning the valves and pieces I use carb cleaner and a little scotch brite pads or brass brush. I lube the valves with 2 stroke oil and the gears with hi temp grease. Good luck with it all.
Greg


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2/14/2018 5:24 PM

i tried following those directions and never got them to work rite then my buddy had his cylinder done by pro circuit and they sent simple instructions i dont have them any more nor do i remember but i bet a call to Pc would get you somewhere

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2/14/2018 6:16 PM

Hey man. I JUST FINISHED my ‘86 and finally got the powervalve figured out. It’s all in the assembly. Your springs HAVE TO be in good shape first of all and you’ve got to make sure they’re adjusted right. I caught wind of this from ThumperTalk and rushed over here lol, just joined and everything. I remeber I struggled for a long time before I got them right. What exactly are they doing or not doing? Is your bike running or still in the assembly stage?

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8/2/2019 5:44 PM

Digging up a thread looking for info. I have an 86 cr250. Trying to put the power valve back together. I believe I have all the parts except the sealing bolt on the rack.
Does anyone know the length of that bolt so maybe I can put a generic bolt in for the correct spacing ?

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4/13/2020 4:41 AM

Reeves516 wrote:

Digging up a thread looking for info. I have an 86 cr250. Trying to put the power valve back together. I believe I have all the parts except the sealing bolt on the rack.
Does anyone know the length of that bolt so maybe I can put a generic bolt in for the correct spacing ?

I've got the same problem. Bought the bike with it missing. I guess it was run that way. Yesterday I ground the threads off the bottom of a bolt and threaded it in. I assume it will work until I can find one. What did you end up doing?

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2006 CRF250X--2006 R1200GS--1984 CT110--1986 CR250R--2005 CRF230F

4/13/2020 7:48 AM

I bet Fellow Vital member StevieD113 can sort you....

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4/14/2020 2:57 AM

sandman768 wrote:

I bet Fellow Vital member StevieD113 can sort you....

Thanks man- sent him a PM this morning!

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2006 CRF250X--2006 R1200GS--1984 CT110--1986 CR250R--2005 CRF230F

4/14/2020 8:29 AM

I'm guessing you guys need the LH side bolt with the extended "nose"? The one you need to swap over to the RH side to set the valves and rack in the correct position?
They are no problems at all! We do them in both Stainless and Titanium, depends which you prefer. If you msg us via FB or email the 'shop we can get you sorted.
The one pictured, I had to make with a bigger (M9) thread as the M8 threads in the RH adjuster side, had stripped out of the barrel, so the STD thread LH bolt wouldn't work. That's why it not finished properly. It only gets used for setting the valves up then it's back in the tool box. Our "production" ones come with either dished or HRC style "flat" heads.
Stevie

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4/14/2020 1:32 PM

StevieD113 wrote:

I'm guessing you guys need the LH side bolt with the extended "nose"? The one you need to swap over to the RH side to set the valves and rack in the correct position?
They are no problems at all! We do them in both Stainless and Titanium, depends which you prefer. If you msg us via FB or email the 'shop we can get you sorted.
The one pictured, I had to make with a bigger (M9) thread as the M8 threads in the RH adjuster side, had stripped out of the barrel, so the STD thread LH bolt wouldn't work. That's why it not finished properly. It only gets used for setting the valves up then it's back in the tool box. Our "production" ones come with either dished or HRC style "flat" heads.
Stevie

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That's the one I'm looking for. Does it serve any function other than to plug that end of the rack? Mine didn't have one when I bought it and Millennium did a replate and HPP service, so I assume it adjusted up fine without it. Will email PDE to get more info. Thanks

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2006 CRF250X--2006 R1200GS--1984 CT110--1986 CR250R--2005 CRF230F