New member/new owner

Tim Ruetten

New Member
Just inherited this from my neighbor. I’ve restored and ridden BMW motorcycles for quite a few years, along with a few John Deere lawn tractors. This is a new type of machine for me. I’m not going to do a purest type restoration. I’m going to keep the patina and just use the bike as intended with my kids.
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69ST

Well-Known Member
Nice score! That's one straight and nearly complete, 4-speed.

If it's running as well as you've indicated, then you've hit the $1000-winning lottery ticket. The engine sat with both valves closed, which prevented the top end from rusting. I've seen this happen before...the engine surviving in a virtually perfect state of preservation, mechanically.

I would recommend tending to the mechanicals, after all, it sat in a wet environment for decades. First thing, pull the wheel assemblies. Replace the tires, brake shoes and bearings; those items age poorly and they are safety items. The rims are spectacularly rusted, not a good thing. If there are pinholes (or worse) in them, replace them. If they're still solid, a trip through the glass bead blasting cabinet will prep them for paint, quickly & effectively. I imagine the brake drum friction surfaces are rusty, too. Hubs don't take much time to blast. After that, $15 worth of silver wheel paint + clearcoat will seal the metal...and make a huge improvement in the bikes appearance. Replacing the fork seals, cleaning the fork internals, then refilling the fork legs with 10W or 15W fork oil will stop the seepage, restore front suspension action and keep the internals happy for another few decades...total cost ~$30. Pull the clutch cover and learn how to clean the centrifugal oil filter; that's the chamber behind the throwout bearing flange. You will need an impact driver to remove those 4 JIS screws. Do not make the mistake of using automotive oil in this engine...or you'll soon learn how to rebuild the clutch. Use JASO-spec, motorcycle oil, labeled "wet clutch compatible". Honda GN4, Valvoline, Castrol are all known oils that have been around a long time.

If you're motivated, blasting & painting the footrest assembly is an easy way to improve appearance, on the cheap. If you're really motivated, the lower fork legs can be metalfinished, lightly polished, then scotchbrited & clearcoated (using the wheel clear), further brightening the overall appearance.

You could throw a new seat cover at this, depending upon the condition of the seat pan & foam. The original latex rubber foam doesn't age gracefully. For the price of new (reproduction) foam & a cover, you could just source a K1 repop seat and be done with it.

I'd suggest carefully inspecting the exhaust. These pipes have a tendency to rot-out beneath the front of the main heat shield mount. This is an easy repair, the rust is tightly localized. It's easy & permanent to weld-on a splice. Then replace the original packing that goes under the mounting clamp. The material used (including the newest OER) is what eats the steel. Use a short strip of header wrap, or packing material from a Cheapie Chinese knockoff muffler. An OEM Honda muffler is a pricey part, since it was discontinued a few years ago. A well-preserved original is now a sought-after item. Giving the muffler a coat of VHT is a good idea.

As long as the engine runs well and the carb doesn't leak, you probably don't need to do anything with the carb. Don't be surprised if that changes. E10 pump gas is not kind to rubber parts (bowl gasket, fuel lines, petcock packing washer), especially old rubber parts. I would replace the airbox assembly. The engine won't last long if run sans air filter. These carburetors are easy to rebuild and yours is well worth the effort, when the time comes. I do wonder how much rust is inside the fuel inlet (on the float bowl), being kept in check by the fuel screen. It's to keep in mind, especially if the engine suddenly begins starving for fuel. As rusty tank can shed.

As for de-rusting the tank, a cleaning with acetone, followed by days of soaking with phosphoric acid should do the job. I'd replace the fuel lines, since the tank must be pulled anyway.

That should get you up & running, with everything working as it should...no bodywork, candy painting or chrome plating involved, patina preserved. All in, figure around $350-400, including a new reproduction seat.
 

Tim Ruetten

New Member
Nice score! That's one straight and nearly complete, 4-speed.

If it's running as well as you've indicated, then you've hit the $1000-winning lottery ticket. The engine sat with both valves closed, which prevented the top end from rusting. I've seen this happen before...the engine surviving in a virtually perfect state of preservation, mechanically.

I would recommend tending to the mechanicals, after all, it sat in a wet environment for decades. First thing, pull the wheel assemblies. Replace the tires, brake shoes and bearings; those items age poorly and they are safety items. The rims are spectacularly rusted, not a good thing. If there are pinholes (or worse) in them, replace them. If they're still solid, a trip through the glass bead blasting cabinet will prep them for paint, quickly & effectively. I imagine the brake drum friction surfaces are rusty, too. Hubs don't take much time to blast. After that, $15 worth of silver wheel paint + clearcoat will seal the metal...and make a huge improvement in the bikes appearance. Replacing the fork seals, cleaning the fork internals, then refilling the fork legs with 10W or 15W fork oil will stop the seepage, restore front suspension action and keep the internals happy for another few decades...total cost ~$30. Pull the clutch cover and learn how to clean the centrifugal oil filter; that's the chamber behind the throwout bearing flange. You will need an impact driver to remove those 4 JIS screws. Do not make the mistake of using automotive oil in this engine...or you'll soon learn how to rebuild the clutch. Use JASO-spec, motorcycle oil, labeled "wet clutch compatible". Honda GN4, Valvoline, Castrol are all known oils that have been around a long time.

If you're motivated, blasting & painting the footrest assembly is an easy way to improve appearance, on the cheap. If you're really motivated, the lower fork legs can be metalfinished, lightly polished, then scotchbrited & clearcoated (using the wheel clear), further brightening the overall appearance.

You could throw a new seat cover at this, depending upon the condition of the seat pan & foam. The original latex rubber foam doesn't age gracefully. For the price of new (reproduction) foam & a cover, you could just source a K1 repop seat and be done with it.

I'd suggest carefully inspecting the exhaust. These pipes have a tendency to rot-out beneath the front of the main heat shield mount. This is an easy repair, the rust is tightly localized. It's easy & permanent to weld-on a splice. Then replace the original packing that goes under the mounting clamp. The material used (including the newest OER) is what eats the steel. Use a short strip of header wrap, or packing material from a Cheapie Chinese knockoff muffler. An OEM Honda muffler is a pricey part, since it was discontinued a few years ago. A well-preserved original is now a sought-after item. Giving the muffler a coat of VHT is a good idea.

As long as the engine runs well and the carb doesn't leak, you probably don't need to do anything with the carb. Don't be surprised if that changes. E10 pump gas is not kind to rubber parts (bowl gasket, fuel lines, petcock packing washer), especially old rubber parts. I would replace the airbox assembly. The engine won't last long if run sans air filter. These carburetors are easy to rebuild and yours is well worth the effort, when the time comes. I do wonder how much rust is inside the fuel inlet (on the float bowl), being kept in check by the fuel screen. It's to keep in mind, especially if the engine suddenly begins starving for fuel. As rusty tank can shed.

As for de-rusting the tank, a cleaning with acetone, followed by days of soaking with phosphoric acid should do the job. I'd replace the fuel lines, since the tank must be pulled anyway.

That should get you up & running, with everything working as it should...no bodywork, candy painting or chrome plating involved, patina preserved. All in, figure around $350-400, including a new reproduction seat.
Wow what a great summary of things to do!! I really appreciate it. I pulled the tank yesterday and used vinegar with a couple handfuls of assorted hardware. Shook and shook and shook and let it soak. Just emptied it and it looks like new inside. The rest I will be picking away at slowly as time allows. I’ve been working remotely from home but I’ll be easing back into the office over the next couple weeks. Back to needing to schedule me time again.
 
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