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Cycle X complete gasket and o ring set

DSC01798.jpgOK here are the parts .Are they oil seals? Where do they go from top left across?
 
Yes they are oil seals. Top left is shifter shaft seal, to the right I believe is the seal in the alt. rotor/starter gear, right top big one is right side crank seal, small one is clutch shaft seal. Bottom row not sure which but one of them is the kickstart shaft seal, far right seal is the output shaft seal. Looks like you will have one seal left. Different years a couple different seals. Just match your olds ones up to the new ones.
 
Thank you. Next question. I took apart the top end. A car mechanic friend after looking at cylinders says to rehone cylinders and get new rings if bad and knurl the pistons on the flat spots. Is this a temp. solution? I want it done right so I don't have to rebuild for a long time.. Can I do this or do I have to bore them? My original problem-bike would not start after overheating at idle too long, I know real dumb mistake. So now I like I said wanted to do the work myself. I lapped the valves already on the head. Do you recommend having machine shop resurface them because of possible warpage?
 
How did the valves look? After lapping did it have a good pattern all the way around? If it doesn't have a good pattern then you need new valves and have the seats cut. You really should have the head checked for warpage also. They warp over time even if not over heated. Chances are your head is warped. NO...do not knurl the pistons. The clearances are to particular in the 750 to use knurled pistons. You run a very good chance of seizing if you use knurling to tighten up the clearance...especially in an air cooled motor, which you should never let idle when not moving for more than a few minutes. Remember airflow cools the motor and the clearances are tighter in the 750 and dont have adequate fin area for no motion idling, they were designed to be moving. Yes Harleys can idle for extended periods when not moving but they have enough fin surface area to allow extended idle periods and are they are actually designed to allow the owner to do so.

If the pistons are scored do it right and get new oversize pistons and rings and have the cylinders bored.
 
Thanks for the advice. I'm glad I brought up the knurling. I'm not sure if the valves have a good pattern. I will post a picture of them. I am thinking of having a bike shop I know of check for warppage and possibly bore cylinders. What should I bore up to? I will need the bigger gasket if I do bore right? This could start to cost alot of money. What is the advantage of rebuilding an old engine as opposed to spending the money on a newer or better shape motorcycle? I coula guess that if you have the tools you could save money in the long run. Starting to question the whole rebuilding thing.
 
You need to measure the bores and determine what size you need to bore them out to to clean up the bores. As long as you stay with the stock Honda overbores you use the same head gasket. When you bore out to 810 and bigger then you need bigger head gaskets. Cycle X can set you up with boring and pistons also. You will be looking at at least $300 for new pistons and a bore of the cylinders. Make sure you dont have the head milled too much because then you will start to run into cam timing issues unless you get an adjustable sprocket. They should take the very bare minimum to clean it up and they also need to check the top of the head to make sure it is flat also because if it is warped or twisted then you will run into camshaft bearing issues.

Honestly if you are not attached to the 750 and you just wanted a cheap motorcycle then you should stop now and look for a newer bike that you like better because the 750 is not a maintenance free fill it up with gas and forget about type of bike. If you like the 750 and want to keep it and modify it then there is a lot of performance parts on the market for the motor but it will cost you some money. If you want a ride it and forget it bike the 750 is not your best bet, they need periodic and routine adjustments.
 
Thank you so much for your wisdom. I think I will move on and find something I can ride without constant adjustments. I do like the 750 Honda motorcycle. I think I need something newer that I can ride instead of wrench Again your posts have help me finally make up my mind. Maybe in the future when I have more interest in rebuilding old bikes I can revisit this challenge. Thanks again!
 
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