Can I use stock 748/9 top triple w/ 748/9 forks on an SC?

[LiveStrong72]

Guys,

I've been pouring over the suspension threads this past week and I haven't seen any of them mention using a 748 or 749 top triple clamp (53mm) with 748 forks. If they have mentioned it, the threads have been light on info. I was planning on shimming the lower 1mm up to 54mm in order to use the stock SC lower clamp. I am not comfortable boring out the top from 50 to 53mm for fear of stressing the metal as it might fail unexpectedly at some point (I've had a front brake lever break apart on me unexpectedly... nearly squeezed a diamond out). I was wondering if anyone had used a stock 749 or 749 top triple on an SC? Things that I suppose would prevent its use would be:

• stem diameter
• width of front fork bores center to center (different from SC?)
• way in which the stock SC stem attaches (press or thread) into the 748/9 top triple
• overall dimension of 748/9 triple (maybe it won't fit?)

Has anyone tried this? Success or failure?

Anything that I'm not considering?

Funds are severely limited, technical skills are limited and machining skills are nonexistent. I appreciate any input you fellas may be able to lend.

I guess I should also ask whether or not the stock 748/9 forks are any better than stock S4 forks (which are direct swap). I had read a comment that said the S4 forks weren't much better than the SC forks. Main reason for looking into the 748/9 option is much better availability than S4/S4R/ST forks.

[Blitzen]

No the sport classic has a unique offset so you can't mix and match top & bottom triple clamps. You could use a bottom triple from a base non-S 748/749. That could be pressed on your stock stem. Of course you'd have to use an sbk top clamp. Note you'll likely lose your steering lock with this setup.

[LiveStrong72]

Originally Posted by Blitzen

No the sport classic has a unique offset so you can't mix and match top & bottom triple clamps. You could use a bottom triple from a base non-S 748/749. That could be pressed on your stock stem. Of course you'd have to use an sbk top clamp. Note you'll likely lose your steering lock with this setup.

Thanks, Blitzen. This is a stupid question but can you tell me what offset means? Is it the distance between the two fork centers at the top? And does this have implication with what rotors and brakes and wheels I run? I ask because I would like to run the same stock wheels that I have now and not have to change wheels, rotors or brakes. Maybe a better way to put this is can I still run the SC stock rotors, brakes and wheels utilizing a 749 top and bottom clamp with 749 forks?

[Blitzen]

Offset is the distance between the the centerline of the forks and the center of the stem. The distance between the fork centers are the same for the SC as for the 748/749. However you the mounting faces for the brake calipers are usually different between the sbk forks and the stock forks (ours is the same as most 50mm shows). sbk forks usually place the calipers 5mm out compared to stock. You will need likely need to space the stock callipers out or space the stock rotors out. There is quite a bit of info in the forum, the trick is finding it with the search.

Oh and sbk forks are usually over an inch or more longer so will noticeably stick up above the top triple. That's one of the reason people go with st/monster forks.

[Kookz]

You can use upper and lower triples and press on the steering stem, but you'll have to come up with gauge mounting. I bored out my upper triple to 53mm, and have 8000 miles, mostly in NYC (probably the harshest roads in the US) since the swap with no issues.