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So I made great progress yesterday on the build and got to putting the jugs back on. I never ordered the damn rings. With my fingers I grabbed the top ring off of piston #3 and it absolutely fell apart. Soooo here I am again with a delimea. I hope this build helps future first timers. All the stuff not to forget! Dirtdigger maybe you can help with this, I went to Honda today and ring sets are $42 per piston. After shipping its close to $200 just for the rings. My pistons are in great shape considering the shape the rings turned out to be I believe I can sell them for a decent price. For $700 ish I can big bore to an 836. I'm a 6'2" 245 lbs guy. I can definatly use the extra power. Also I have a non-running 1980 cb650 headed to my garage in 3 weeks. So haha my question is should I shell out the cash to big bore it since its all apart? Or get her running proper like Honda intended it to? I'm looking for pros and cons of both ideas. Thanks all!
Well if you rering the standard pistons it will run good, maybe pop a slightly bigger cam in it and you will have a good runner. The 836 is a good reliable motor. To take advantage of the increase you really need a cam to go with it and if you want it to run really good you need to do some head work. If you do just the 836 without at least a cam you will probably be disappointed with the increase in performance, you will gain some but it wouldn't be huge. $700 is kind of high for a 836 big bore. Cycle X has there 850 piston kit for $250 and bore the cylinders for another $150 then get a bigger cam for $200 and matching springs about $60. But any 750 I would do heavy cylinder studs and heavy duty cam chain, $80 and $30 from APE. Wiseco 836 piston are $200 higher than the Cycle X piston set but the Wiseco are forged and the Cycle X are cast. The cylinder head is where the big increases in power come from in the 750 motor but it will cost you some $$$. You can make the stock 750 run really well with a cam and good exhaust with appropriate jetting and good tuning of the ignition system. Yes building the 750 to really run is expensive but it is kind of addictive too. lol
I was thinking $700 for big bore, boring and whatever else I needed. Ill take a look at getting a cam, cycle x kit and the higher performance springs.
Will my stock cam chain and cylinder studs hold up and work well with the above done? I know it's a slippery slope. If I go that far I might as well port and polish the head. I want to stay under $1000 and have a great running machine.
Thanks DD
Will my stock cam chain and cylinder studs hold up and work well with the above done? I know it's a slippery slope. If I go that far I might as well port and polish the head. I want to stay under $1000 and have a great running machine.
Thanks DD
People get by with the stock studs and cam chain but you are increasing compression and making the cam chain work harder with stiffer springs. The stock chain is kind of a weak spot as are the studs. Did you replace the cam chain? If not I would say dont use the old one with the bigger cam and springs. I never build a 750 motor without a heavy duty cam chain and heavy duty studs whether it is stock or high performance. Are you handy with a die grinder? Even touching up the ports in the head make a good increase in flow. I port most of my heads myself but I have a home made flow bench to test what my grinding is doing while I go. There are specific places in the ports you can easily touch up yourself that are really bad restictions and make noticable improvments. You will be looking at $700 minimum to get the head ported by someone and may be more if guides and or valves are worn. Speed costs money how fast you wanna go!
