Shortening my wheelbase?

[ffs1942]

On RAGBRAI I met an old Colnago riding Texan who enlightened me as to what the adjustment screws on the rear dropouts are for.

He says they can be used to lengthen or shorten the wheelbase.

I have a circa 1985 Schwinn Tempo. A beautiful oldskool bike, but am having trouble keeping up with newer bikes-OK, yeah maybe I just need to ride more- and need to maximize the design.

Since I got the bike used 10 yrs ago, it is missing the screws. I place the rear wheel all the way back, so it has quite a ways before it rubs the chainstay crosspiece.

What will happen if I move the wheel up 1-2"?

I know presently my Tempo puts more wear on its rear tire than any previous 10 spd I've had. The first bike I had to rotate tires on.

 

[531Aussie]

I stuffed around with this years ago, and I figure it's not worth it, and I'd be surprised if you have 2" to move, unless you're talking about a very old 'fixie' (no derailleur hanger), by which case you'd have to shorten the chain

the differences with moving the wheels way forward are barely noticeable, and i was told that if the wheel is too far forward, it puts more stress of the front of the dropout and the chain-stay -- maybe that's why i cracked mine. For strength, my understanding is that the axle is best placed pretty much directly under the seat stay.

you shouldn't need the screws to hold the wheel where you want it

 

[John M]

On RAGBRAI I met an old Colnago riding Texan who enlightened me as to what the adjustment screws on the rear dropouts are for.

He says they can be used to lengthen or shorten the wheelbase.

I have a circa 1985 Schwinn Tempo. A beautiful oldskool bike, but am having trouble keeping up with newer bikes-OK, yeah maybe I just need to ride more- and need to maximize the design.

Since I got the bike used 10 yrs ago, it is missing the screws. I place the rear wheel all the way back, so it has quite a ways before it rubs the chainstay crosspiece.

What will happen if I move the wheel up 1-2"?

I know presently my Tempo puts more wear on its rear tire than any previous 10 spd I've had. The first bike I had to rotate tires on.

Although you do not need the screws to keep the rear hub in the right place, if want to get replacements, you can order them from Loose Screws:

http://www.loosescrews.com/index.cg...sting Screws&item_id=LS-0102SF&id=94260671275

 

[DiabloScott]

Although you do not need the screws to keep the rear hub in the right place,

The screws are to get the wheel back in the same place after you take it out. Adjusting how far the wheel slides into your dropouts is for better derailleur operation, once you find the best spot you set the screws there so it remembers where to go.