opinions requested on my motor

[sbaugz]

So I purchased a 1975 T500 locally. It was a complete mess from sitting outside for 10 years. Hadn't been started in a while. Totally unridable as is due to rotten tires, no brakes, etc.

Before I get to my question, I will tell you a little about myself because I believe its pertinent to my question.

I have built maybe 6-7 cafe racer bikes. They have been featured on popular blogs, magazines, etc. I know my way around motorcycles with one exception-the engine guts. All the bikes I have made came from well running donor bikes that I knew were reliable, so I never had to rebuild one. I can do points, tuning, carb rebuilds, valve adjustments, etc---- but I have never had to rebuild an engine (with the exception that I replaced the piston rings on my XS650). Which leads me to my questions.

I have this T500 as described above. I rebuilt the carbs and got the bike running in my garage. Its seems to run, idle, and rev up nicely. I checked the compression and both cylinders were 145 PSI cold. Meanwhile, I have completely stripped down the bike, had new wheels build up, forks are getting rebuilt after the fork lowers get back from chrome-er. I ordered a ton of NOS parts from Paul Miller. I am getting ready to order Jemco chambers and Titan rearsets.

While I wait for chrome and powder coated bits, I have turned my attention to the engine. It is literally coated in an inch of grease, grime, and sludge as hard as granite. Every nook and cranny is completely coated in this crap. I can't even tell if anything is leaking or not because of all the crap everywhere. There is even a petrified wasp nest underneath engine. I am spending a decent chunk of change on all the other parts of this bike and everything will be basically new. I wonder what I should do to the engine? I am having a tough time getting all the crap out of the nooks and crannies. I have never completely rebuilt an engine before. I feel like I probably could handle it, but I am not sure. Would it be better to take jugs off to check out things and get them cleaned better? If I take jugs off and the pistons and sleeves look ok, what am I obligated to replace? Just the head gasket and rings? Why stop there? should I get the crankcase rebuilt while I am at it? I haven't been able to drive bike due to condition, so I cannot comment on condition of clutch, gears, etc.

Part of me just wants to do this right from the beginning. Unlike my other bikes that I have built, I am keeping this one. I am tempted to just send the engine away somewhere to have it completely rebuilt but I don't know where or who to send it to? What can I expect to pay for a complete rebuild?

Sorry for the rambling. I am looking for advice as to what I should do. I am located near Milwaukee. I would also be interested in name or places of reputable rebuilders.

[ConnerVT]

Sounds like a nice project. We require pictures. Lots of pictures. Because we enjoy them.

The good news is, while it is "The bike they said couldn't be built", the motor is really very simple and easy to work on. So it is a good choice for your first time to handle the "engine guts".

More good news is that for a 40 year old motor, virtually all of the parts you need are still available from Suzuki (gaskets, seals, etc.)

You have the carbs cleaned, the engine runs, and (so far) no complaints about how things are working. Your worries about leaks can be relieved, as the only fluid the bike holds in the engine is gear oil for the transmission (1400cc for yours, disregard what might be stamped on the engine case).

So the question: Do you take it apart, and if so, how much? (OK, two questions).

I would probably start by taking the engine off the bike. With the carbs and front sprocket cover off, power wash the hell out of it. De-greaser and a brush, clean it up as best you can. Then the question is, it it shiny enough for you?

If not, the three side covers (sprocket, electrics, clutch) can be stripped of clear coat and buffed. The jugs and heads can be blasted, and if the cylinder walls are good, would just require rings and gaskets. Blasting the cases would require opening it up, and pulling out the "guts", but is not really that complicated, with some mechanical knowledge and a shop manual.

My T500 was also the first motorcycle engine which I held the motors guts in my hands. I've shared the story hear before, but I had finished rebuilding it, and brought it upstairs to the garage and put it on the bike. was waiting for my bother in law to arrive with his compressor, so I could use an impact wrench to put the clutch and sprocket nuts on. Then I realized I had the crankshaft in backwards. I pulled the motor back off the bike, pulled the cylinders off, split the cases, spun the crank around, reassembled the case, reinstalled the cylinders, and got the motor back onto the bike, all in about 2 hours. Worst part was carrying the assembled motor up/down the stairs!

[titan performance]

From what you have said, you have a good running motor, and with 145 lbs per pot, it would appear to have a good top end on it. I had my engine cleaned recently, and although probably not as bad as yours, it was pretty grubby. I sealed the ports up with some rags stuffed in, and then silicon over the top to totally seal them. The entire engine was then soda blasted, which removed all of the gunge.
I polished the outer cases for a top job.
I would fit the motor and try it before spending my hard earned....these are tough old lumps and you may well find there is nothing wrong with it. If however, it's not good, getting it back out is fairly simple.

[sbaugz]

Thanks for the advice. I think I'll clean it up as good as I can and see what happens as is without touching anything inside. I didn't mention, all the side covers are off and already at the powder coater. I thought about having them polished but that's too much shiny bits for me. I already have polished wheels and shocks and exhaust.

I will get more pics soon. Only one I have now to share are a few parts after sand blasting. The side covers are getting black powder coat, the brake drum plates are getting polished and the fork lowers are getting chromed

[Vintageman]

If you want a little more Horsepower, look for a set of pre 1973 cylinders: the ones when you look into intake have no aluminim divider.

Make sure the small end connecting rod eyes have no rust stain stripes due to moisture pooling under needle bearings for example. Oxidation always a concern when it gets inside motor

[Coyote]

Short of blasting, the only thing that will soften the layered crud is gasoline, and a good stiff round brush. I just re-did a 76 GT550. I think the last time it was cleaned was 1976.. Thick - really thick layers of gunk that only a 2 stroke can produce. Kerosene worked but was too slow so I graduated to gasoline. E-10 Biodegradable cleaners are worthless.