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Discussion Starter #1
Folks,
I'd appreciate some advice. My '74 CB360 has been slowing down, leaks oil all over the place, and its time for a long overdue engine rebuild. While I have her all apart I am thinking I would like to bore out the cylinders and increase the stroke. I know some things about engines and machining, but I've never upped the displacement on a bike before. I'm trying the figure out the price point for whether and to what extent to do things myself vs. taking it to a shop. I'd appreciate any advice on a good supplier for the kit parts, and/or a good shop for some of the machining. If anyone's done this before, please give me a shout. Thanks!
 

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i dont know that anyone makes rods or a crank for the 360. or hp pistons for that matter. not that you couldnt have anythng you want made. and not that there isnt something out there already that could work. i know mike ran a cam, ported head, carbs, and bigger intake valve on his with stock pistons and it went pretty good. hed probably know more. you could also try searchin it here.

its been hashed over a few times.
 

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Yep, my thoughts exactly - bore's fairly easy to accomplish, but stroke would be tricky. Wiseco's probably got a pistons, or at least blanks, that are close enough to get you some added displacement. You can probably safely lose in the neighborhood of 3mm from the piston sleeve, getting you somewhere in the neighborhood of 390cc... but I'd take the cylinders to a decent machinist and get their opinion before ordering pistons.

I'd have to guess the power you'd make with increased bore, direct linkage carbs, a better air intake setup and proper exhaust would easily match the added power of a bit more stroke, and would almost surely be cheaper than having someone turn a crank and forge (or modify) rods.

If it's power you're after, other options include stuffing more engine into the bike... I'd bet you could get a pretty monstrous 2-stroke into that space.
 

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and fil out yer bio. where do you live??? that might help a litle. if it were me, id bore it, stock oversized pistons, bigger intake valve (same as the 350) hd valve springs keepers retainers, port and polish the head, couple of mikunis, and a cam, with a pipe, which is easy off the shelf from mac, just send it out to jethot before you mount it up, and a decent clutch and springs, run an electronic ig, and you should have a pretty nice little rocket that will run for just about ever.

jc
 

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joe c. is dead on but for shear balls I like the big 2 stroke idea. Yamaha made a 360 if you're married to that displacement. If you go the 2 stroke route be prepared to upgrade everything else on the bike, underware included. cheers, bcr
 

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Don't waste your time on a cb360. Sell it for more than you paid and buy a cb350.
 

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Discussion Starter #7
You have all been very helpful, and as a result I am seriously considering the strokeless route to more performance. A guy from Crower http://crower.com/ did say he could get me parts for pretty much any ratio I wanted though.

Two last questions: Where can I get me some Mikunis and why is the CB350 a superior bike?

Thanks
 

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the 350 is only better because someone hasnt done the r&d on the 360's. there is one person who can pretty much be credited with the big developments of the cb350 and thats todd henning. and that was only through the close initial supervision of supertuner kevin cameron. the 350 hipo stuff was developed specifically for racing in a certain class. the 360 was never competitive in the classes it would run in strictly for hp/disp/date issues. so the 350 is what got the treatment. personally, i think if anyone was to spend as much time and effort on the 360 as the todd/kevin combo, with the other people who had also added to the effort you could have a kller 360. with a 6 speed even. just because its not don, or easy, doesnt mean its not possible. the 1mm intake for the 360 is the same 1mm intake valve for the 350.

personally, i like the feel of the 360. its heavy, steers well and is roomy. it made a fantastic endurance racer when we did it. my 350 by comparison is a scalpel.

just my opinion.
 

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having owned a 360 and ridden several 350s, the 350 is just out of the box faster. 360 is a good street motorcycle that is smooth but the 350 is a performance small twin. +1 on todd henning and the R&D on the 350.
 

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that 360 is so illegal for 350. and in my hands theres no way i can beat a 350 as hot as yours.

that and i dont know the current state of the 360. mike used to kick ass on is 360 racing it when he was a young lad.

jc
 

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The 360 currently needs a crank. I have the parts but have not yet had the time nor inclination to put it back together. It will happen some day though.

Mike O.
 
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