Mychal's 91 CR500 engine rebuild.

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Sandblaster
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Mychal's 91 CR500 engine rebuild.

Post by Sandblaster »

The list of parts replaced is more then I want to type out :shock:
I'll just say that this is more then piston and crank kit rebuild ...
First off many of the trans gears were so worn it was amazing that they worked at all.
The first big hurdle was finding another trans as most of the gears are not available new from Honda.
One was purchased off of eBay and it was junk so it went back to the seller for a full refund.
So Jason (The engine builder) and I sat down and figured out what all gears to to be replaced to upgrade to the 97 transmission.
Yes, the shafts are the same....
So, a bunch of gears were ordered from Honda.
Before anything was done we cleaned the cases in the extreme, painted them with VHT engine paint and baked the cases.
Then assembly was started..
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Sandblaster
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Re: Mychal's 91 CR500 engine rebuild.

Post by Sandblaster »

I told you it was clean... 8-)

All new bearings, seals, bushings, spacers, snap rings, ect.
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Sandblaster
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Re: Mychal's 91 CR500 engine rebuild.

Post by Sandblaster »

More assembly..
CR500 ENGINE ASSEMBLY WWW.OEM-CYCLE.COM 101.JPG
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CR500 ENGINE ASSEMBLY WWW.OEM-CYCLE.COM 102.JPG
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Sandblaster
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Re: Mychal's 91 CR500 engine rebuild.

Post by Sandblaster »

Well... here is the finished engine.
Sure it's clean and purdy, most everything inside has been replaced including upgrading the transmission with newer gears so that it is now at 97-01 specs, but what really makes this engine nice is the Adam Millar ported cylinder along with his special head mods and decomp.
Yeah, this one is gonna be a real runner...
OEM-CYCLE.COM CR500 FULL REBUILD 103.JPG
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OEM-CYCLE.COM CR500 FULL REBUILD 104.JPG
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MikeCR5
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Re: Mychal's 91 CR500 engine rebuild.

Post by MikeCR5 »

I have it most of the way together now just waiting on a few things. I ran it through about 10 heat cycles before taking it out. I've been trying to break it in nice and slow so I haven't done much with it yet but I have ridden it a few times. The first time for about five minutes, got it warm and went through the gears. Second time I rode it around the fields for about 10 minutes and yesterday for about 20 minutes. So far it feels really good. Transmission is nice and tight, idles beautifully starts fairly easy and accelerates good. I haven't really hammered it get but I can tell I will need to play with the jetting some. Right around half throttle it has a cough and sputter thing going on. The plug looks good though. I will likely get back with you and Jason soon to see what I should do with it next. All in all I'm very happy with it so far and I really appreciate all the help from you guys. If not for all yours and Jason's help it would have probably just have been another part out. Instead it's a heck of a motor. Now I have to bring the rest of the bike up to date
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Sandblaster
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Re: Mychal's 91 CR500 engine rebuild.

Post by Sandblaster »

Yeah, make a appointment with Jason and bring it down and he will help sort out your carb issues.
He's really good with jetting.
I can't wait to get that thing out on the dunes to see how well it performs..
Looking into suspension upgrades 8-)
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Re: Mychal's 91 CR500 engine rebuild.

Post by Sandblaster »

Ok, on the forks, the bottom triple clamp bearing fits up to 01 CR500 and many years of CRF450R's.
The top bearing fits up to 01 CR500 but no year of CRF's.
So you could install forks off a 01 CR500 with no issues.
The 450F forks are still in question...

96-01 CR500 forks have the following clamping diameters
UPPER CLAMP 52.8MM
LOWER CLAMP 58.8M

02-08 CRF450R forks have the following clamping diameters
UPPER 52.8MM
LOWER 58.4MM

Looks close enough...
I think you could bolt up the CRF450R forks to the 96-01 CR500 triples...
So you would need a front axle, front wheel, and front brake caliper and mount.

I will try to confirm all that...
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Sandblaster
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Re: Mychal's 91 CR500 engine rebuild.

Post by Sandblaster »

Looks like you can run up to a 01 cr500 rear shock as long as there is enough clearance at the bottom clevis 8-)
I have some CRF450R shocks that we can check the fitment on as well....
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Sandblaster
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Re: Mychal's 91 CR500 engine rebuild.

Post by Sandblaster »

Make a appointment and bring it in and lets see what it will take for the rear shock.
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MikeCR5
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Re: Mychal's 91 CR500 engine rebuild.

Post by MikeCR5 »

Yes the forks is the next thing to upgrade. I've been keeping an eye out for a whole or as close to whole front end from a 96+ bike. They are supposedly a significant upgrade and I don't need state of the art, but better would be nice and it would be the least expensive option
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