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Discussion Starter · #1 ·
I'm just curious as there are, in my neighborhood, more bikes out there without titles or are legit "parts bikes". So it seems that piecing a bike together might be more feasible than finding exactly the right bike.

Specifically, I like the SL frame and I know that motors are somewhat different in physical size versus displacement so this probably would not be brain dead simple, but would (for example) a 350 motor even fit into an SL 175 frame?

Are there some swaps that would be impossible/stupid, some easier than others? Any generic guidelines you can offer up?
 

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Sensei
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If you get an SL 175 frame, you can use a CB/CL/SL 175 or CB/CL 200 engine....Possibly even an XL 175 (or XL 250) single cylinder engine.....
A CB/CL 350 engine will NOT even fit in a CB/CL 360 frame, although a CB/CL/CJ 360 engine can be installed in a SL350 frame....WITH some minor mods....
I too like the frame/tank design of the SL bikes, so here is my version of what CAN be done....


It's a trial and error scenario...... Steve
 

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Discussion Starter · #3 ·
Nice looking bike, sexy and mean. I'm thinking more along the lines of dual-purpose, backroads traveler.

So basically you're saying NO to larger motors into smaller frames. So I guess putting a 350 into a 250 SL is out also?
 

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Sensei
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I wasn't aware of a US version SL 250......However, the early "euro" and "general export" 250 twins were in essence underbored 350's ....THAT might/should be do-able..... Somewhat like the CL72/CL77 interchanges..... It's NOT the displacement differences that are a problem, it's the physical size/weight differences that matter.....Plus, of course the strength of the frames.....
 

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Steve, I thought the reverse was true, that a 350 engine could be coaxed into a 360 frame (with new mounts) but not vice versa? I swear i saw someone's project log who did just that. You'd know better than I would for sure though :)
 

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Sensei
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Pic above is a CJ 360 engine in a SL 350 frame....... You CAN get a 350 in a 360 frame if you cut/modify and reweld a bit... (not recommended though).... it's the lower cradle you have to alter, not just bracketry....
 

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Discussion Starter · #7 ·
66Sprint said:
I wasn't aware of a US version SL 250...
It was a CL ad, and who knows how accurate they are? That's why I'm asking these questions here as I sure as hell don't know.
 
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