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I love the ingenuity! In my opinion there is no downside to installing a decomp button. You'll hear some guys say "if you need the decomp button then maybe you shouldn't be riding a 500 blah blah". Yes we all can start a 500 without it, but if you're racing, on lap 4 and you fall and stall the bike, the last thing you want to do is to kick over a nasty 500 lol.
I measured the bore on my cylinder. It measured at exactly 3.55 inches which is 90.17 mm. There is no ridge at the top which is baffling to me since the bore is obviously worn. My guess is that this bike is on piston #3 , or #4 and at some point a previous owner cut the ridge down.
Looks like you are on a 90mm piston.
That number I don't recognize - perhaps it's an old Wiseco code, or some other brand?
I wonder what put those Dings on top of the piston?
With a few brands, you've got another 2 re-bores. 90.5, and, 91, which gets to 513.8cc. You mentioned a 520cc from Millenium - they might have got a batch of 91.5s made? Good to know for a few people, if so, to get another re-bore in before a re-line. Perhaps they have a 92 for 525cc?
Wiseco list the same piston code from the 480, through to the last of the 500s in 2001 ( well 2002 in the case of my CRE ).
Wossner, which I use - Much Lighter than the Wiseco - list 3 different piston numbers, from 82/83 480 - though, it just has the 'A', then 84 480s have the same # with the oversize, then 85 to 2001. And, I think, 2 ring or single ring pistons - I use the 2 ring.
Watch out for ProX - they had a rep for having too narrow a piston body at the wrist pin, leaving the exhaust ports open. Though, I daresay that may have been sorted over the years.
In all the Massive Hours and Ks I've done on my CRE, I've only had to go to 89.5mm. I think I achieved that by feeding it all the std ( I think around 5 or 6 of them) Spares Kit pistons I had from my CRs, and and a few Mates spares kit left overs. I was very miffed at the time to find it was just over being able to use an 89.25mm piston I had as a spare, that I had from years before...... 🙃 Running Fans and bigger ( in fore and aft depth) radiators, plus a few Water Pump mods have probably been a big part of it, though.
Nice work!! She's going to be a beauty!
I sent everything out to millenium. They are going to install a decompression button while they are in there.
I tried to polish the lower fork tubes today. Lots of elbow grease. The factory Honda lowers have a clearcoat of some sort on them. It's gets beat up over the years. 320 grit cuts right through it. I did 320, 400, 800, 1000, 1500, and 2000. Then a liquid Mothers mag and aluminum polish and a buff with a microfiber towel. They look great but the deep scratches get amplified.
Then I got carried away and decided to powdercoat the triple clamps. I did them in chrome, and then with a clear coat. I think I put the clear on too soon because when they came out of the oven they look silver now. I think the clear just blended with the chrome. I'm going to do them over.
Here's the fork tubes.
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Millenium will do a decompression valve for $149. That seemed like a no-brainer for me. I didn't see it listed on their website but the salesman I talked to said they do them all the time. He was very well versed in CR 500's. He said that they do tons of them. My parts will arrive to them Wednesday. The "kit" I got is $593. They bore/hone the cylinder, machine the head for squish and set for whatever fuel you use (I'm going pump 93). New piston, rings, wrist pin, gaskets, and shipping included. That's also assuming my stuff is usable.
If your looking for rims look up Rimsplus. I got Excel Takasago in blue and kinda burnt bronze hubs for a price that nobody else could even get close to.
I'm going to go with Full Circle Racing rims again. I'm using the stock hubs. I'll likely get new spokes as I had to cut a bunch. The Excel "gold" doesn't look right on the vintage bikes. I looked at the Rimsplus stuff a bit. They have instagram, facebook, and mxlocker but no regular site with pricing that I could find. I can get the Full Circle rims for around $190-$200 each.
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