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Tore into the engine today. It's still on the original piston! Still has a decent amount of crosshatch in the cylinder but both rings were out of spec. I found a set of NOS Honda rings. I'm going to lightly hone it and reassemble with new rings. The reeds look immaculate. Someone had the head off for sure as there were telltale scrape marks on the piston dome. Also a brand new head gasket. Crank looks good,with zero up and down play. Overall I'm pleased with how it looks. Just going to scrub it down and paint everything.
Got some cleaning and polishing done today. I love working with aluminum!
I'm waiting on some parts to arrive so I tackled some tedious stuff today. Cleaning and polishing the spokes. I did the front spokes. Easiest way to make them look amazing is to chuck them up into a drill. Spin the spoke up real high and wrap sandpaper around it. I go with 320 then 800, 100, and finally 1500. Each spoke takes about 1 minute to do. They look brand new when you're done. There's a pile of done ones next to the last 2 unfinished ones just for comparison.
480's blow base gaskets on an (ir)regular basis. Keep a spare on hand when you take it to a track. Otherwise, both the '82 and '83 are very reliable. I'd love to have an ignition with 2 settings - one for starting, the other for riding. You can add a Maico-style compression release in the back of the cylinder to make starting easier. There was a machinist in Ohio that used to bore/tap it for a reasonable price. Excellent handling bikes. The 480 engine fits right in to a 1980 CR250 frame, if you want to make a twin-shock version. I had an RC500 replica aluminum tank built for one of mine by Holly in Japan. I prefer the 480's over a 1981 490 Maico, as they sit lower. 490's power is a little stronger, but the 480 is easier and more fun to ride. Hope you enjoy it!
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I will take your advice on the base gasket! There is a company that makes compression releases for kickstart Harley's, that simply screws into the plug hole. You have to modify your spark plugs for it to work, but it's a fairly ingenious solution.
https://www.wimmercustomcycle.com/compression-release-kit.php
I don't know if would clear the fins though.
Rick Merhar is the guy that was doing the compression release kits:
Accu-Products - Big Bore Compression Release Kit
I owned and raced a 1983 CR480R, didn't ever feel the need for the compression release for this bike. My 1987 CR500R, that could have used one...
This would be an excellent thread topic, Joel! I think a lot of people would be interested in building a powder coat oven, or learning how to powder coat smaller parts in an old oven.
Decided on a color change for the rear shock. It was red from the factory but I think blue looks better. Has more contrast to it. I bought some Ford Grabber Blue and went to town. It came out great. I'm clear coating the subframe as well.
Subframe went to crap lol. I don't know if the oven got too hot or what, but the color is all mottled and different than the main frame. Oh well, I'm not blasting it and doing it over again. You can only see a few sections of the subframe when the bike is together anyway. I mocked a few parts up. Next week the engine "should" be back together and in the frame.
Henry Gref machined my cylinder for a Maico-style compression release in the back of the 480 cylinder. The activation lever goes on the handlebars, and it's very easy to use. One of my 480's has the Harley-style compression release in the cylinder head. It automatically deactivates after each kick, and I have to walk around the bike to reset if each time I kick it - very inconvenient.
You should be able to kick it with your left foot though lol. So you don't have to walk around the bike each time.
With the 'Big Twin' type pop off valve, did they put it at the rear of the barrel like what I see so often with what you call the 'Maico -style' decomp?
Or, on top, in the head?
I was puzzling over where one could put a Pop Off Decomp, with the old 'Finners'.
I've done all sorts of Decomps over the years - the ancient 'out in the breeze' ones, that you refer to as 'Maico' style, Pop Of Big Twin / HD types, and 'Lawn Mower' type, Vacuum operated ones - I've such a thing on my CRE, but, that requires (on a WC cooled bike, when through the head) making a holder, that is then welded externally, and within the head. With that, I just kick the bike, with No faffing about.
Grotty old pics of what I refer to :
Here's apic of what someone came up with to operate the Pop Off Decomp from the bars, but, of course, on a WC head :
And, here's the Wimmer Decomp set up, that the Spark Plug goes into ( you have to do a 'Transfer' port - as shown - to a section of the plugs thread, and, I guess, a longer reach / longer threaded plug may be required?
I don't know the 'Finners' that well, but, looking at some 480 pics just now. , with the pipe to the LH side of the tank, it looks like either the Wimmer ( perhaps with no fin trimming) Or, a Pull Type Decomp by itself, could go forward / near the original plug area, with minimal fin trimming?
You often get 'Real Men' going on about there being no need for a de-comp : a Huge benefit can be simply the life of the KS components / the Cases. There's a Massive amount of load / shock applied to All of those parts, if not through the force of acting against compression, it's the almighty HIT, of the KS lever against whatever final stopping mech is.
One of my 480's came with a Harley-type pop-off compression release. It's in the head, on the right hand side.
That Wimmer setup looks promising but I'd have to see if they would clear the fins and also with it pointing straight up if it would be feasible under the tank. I see you have some that seem to be on a 45 degree angle though.
Looking at a fair few pictures of the 480 head, I'd say that 'newer' Wimmer cast / machined adapter would have no problem with fitting.
Well no problem if you were to trim that fin that is outwards from the plug, at the forward section of it.
The Spark plug , as standard, can be got to from under the tank, so therefore, the Decomp, whichever route you take, being very slightly forward and outward of it, would be direct to hand.
The vertical 'upright' of the Wimmer item, could be oriented slightly forward of the plug, and, you could have the fin cut to just allow it, and the fin could be a convenient stopper for the adaptor when tightening the Spark Plug up.
Of course, with the adaptor set up, you then have to sort the version of the plug, for length / reach / projection, then machine a transfer port into it.
But, with what I would think is minimal fin trimming, well, a machinist could easily machine a port directly into the head, to take the Big Twin / Pop off valve Directly into the head. I've used the ones that are a 10mm thread - there may be even smaller, 8mm ones? With that , No faffing about with 'special plugs' would be required
If anyone is / would be concerned with any heat shedding reduction, from (probably) around 15mm of vertical fin removal - well, look at the fins on the exhaust side, made to clear the pipe, and, the KS lever.
I may seem blasé' about this, but it's pretty bloody simple stuff.
Decided to install the engine today. My Specmoto bolt kit didn't have the bag with the cylinder nuts or head nuts. I sent them an email and the parts are on their way. Engine went in with the help from my GF as it's hard to hold up an 80lb engine and finesse a bolt through. I'll go about replacing case bolts sometime this weekend.
This appears to be a straightforward restoration. Wha1t did you mean by calling it a "RestoMod?"
Cone pipe, silencer, bigger pegs, gold anodized wheels, better bars, better throttle, better tires, etc. Nothing crazy, just a slightly molded stock-ish resto.
I come from the musclecar world. You don't dare call a slightly modded musclecar a restoration unless everything is period correct. The zealots will go nuts.
Pit Row
Forgot to post some internal engine pics. The bore looked pretty good. I took out both rings and measured them. They were at .024" which is right at the service limit according to the manual. I jumped on eBay and found a set of OEM Honda rings for a CR 480 for cheap. I installed them after a mild hone and got. 017" which is good to go! I polished up the handlebar mounts and changed most of the outside engine bolts to new specmoto bolts. This weekend I will tackle a lot of stuff. I have new rims from Full Circle Racing coming in, and a full plastic kit from VMX coming in. I have 2 new Hoosier tires to mount as well. Then it's just a bunch of odds and ends to finish it up.
Having both a 480 with the head-modified decompression valve, and another with the cylinder-modified Maico type decompression..., the Maico-type works much better. Neither bike has any heating issues that I've noticed.
Did some small bits today. Got the rear brake pedal and cable all polished up. Did the swingarm caps as well. Also cleaned up the Honda wire clamps, and bolted up the cdi box and coil. Bikes look so fresh when they have the correct clamps instead of zip ties.
That tab / extension to the RH side Swingarm end 'cap' : I'm wondering, is it a 'bit' to stop the chain from going down into the brake / backing plate (during just routine maintenance, I'd think), or, could it be a back up if say, the brake torque arm breaks, the backing plate then rotates, and you'd still have brake (at least for a tiny amount of time) ?
A lot of bikes over the years, have had neat little things, to stop / minimize potential problems.
I personally liked the vertical nylon plates on Swingarms towards the front, that a fair few Honda models had for a few years - so much so, when I PDS'd my CRE500, I put some mounts on the swingarm, to fit a plate I made from some nylon breadboard. Saves my shock protector, and my alloy airbox, plus, makes things much quieter when doing transfer sections on rides / during Enduros, when a chain can resonate / chatter at certain speeds, while cruising.
I honestly don't know what that extended cap is for lol. You could be right on your assumption.
Bike Is getting real close to the finish line! My VMX plastics arrived. The fenders and side panels are GORGEOUS! They absolutely nailed the color, finish, gloss level. The front number plate looks a little weird. It will probably look good once it's on the bike. My gold rims will be here Tuesday, then I can build the wheels and wrap it up!
Headed to the Zoar Valley MX Reunion in 2 weeks!
Did some more tinkering. Got the cone pipe and silencer on. I'll have to fab up some sort of mount for the top of the pipe. The previous owner broke it off and then welded a nut to the frame but it's in the wrong location. Cleaned the carb and installed it as well. Bike is ready to fire.
There's a YZ125 carb that works well on the 480. I'll look for the model.
The rims came in and look amazing! Was able to lace up the front wheel. Will probably do the rear tonight or tomorrow, then I'll true them both.
In the home stretch now. Got both wheels built, tires mounted, plastics mounted, some decals on, levers on, brakes all adjusted, and footpegs on. Ran into a few snags. The footpegs fit like crap, they sag down a little. I don't have time to come up with a solution. The number plate decals are cheap. They are too thin and don't stretch enough. The rear axle is a hot mess. At some point in the past 40 years someone took a sledgehammer to it. I ant get the nut on. When I bought the bike it had a hose clamp holding the axle on.ill try to get a 18mm die here to clean it up. Still have to fab up an exhaust mount, and then get the throttle working. I'm trying to run a motion pro vortex throttle with the factory cable. The cable doesnt have enough slack in it. When I assemble the throttle it's giving it 1/8th throttle. I'll figure something out. Here's a few pics.
There's a rear axle and nut on ebay...
https://www.ebay.com/itm/256360126163
Thank you! I just bought it lol. I bought an 18mm die which got here today, and I can't even get it to bite on the first thread. I'm thinking I could take a band saw and cut off the 1st 1/4" of the axle, but then I'd have to clean up the end a bit. My axle is slightly mushroomed out. Got the new chain on, modified the throttle to work, got the grips on. Should be running later today. Just have to put the front number plate decal and right side panel decal on. I'm going to let my GF do it. Then I'll take it for a rip!
It's alive! Runs real strong. Fired on the second kick. It would have fired on the first kick but it caught me off guard lol. I had to take the rear axle out of my other 480, but I'll swap them out when the new one comes in.
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