Front rotor

[chronoman]

I'm in the process of redoing my brakes on my GS450 1987, and I noticed that the front rotor has some deep groves, can they be turned? and if so where do I find out what is the limit as far as thickness once is turned on a lathe?
Would a rotor from another gs fit? and has nay of the 450s ever came with dual front brakes, mine has mounting points on the right side as well as the left.

[twistedwankel]

Do a search on "brake rotor" as there is tons of good advice and directions there.

I got my used "spare" set of front rotors off an ebay MC store for used parts cheap. They are excellent. My 81-750 has dual front rotors (way overkill) and shares the same front alloy wheel with many bikes.

I don't know the min. thickness limit in specs? I don't have access to a rotor lathe anyway. Many times they are stainless and it is almost too hard to turn them with normal tooling.

I had what appeared "visually" to be rough rotors but when I cleaned them off with alcohol and ran my finger nail over them they were still very smooth (optical illusion). Put on new pads and they polished up by themselves within 400 miles and are beautiful now.

That's why many of us change out our pads way early to avoid the expense of new rotors. My front pads cost $30/set each side as I had to pay full retail locally. So with no labor it was $60 with no rotors or labor.

Maybe your rotors are merely contaminated? Don't clean them on the wheel with brake cleaner as it will take off the paint....

If not a rush issue you should be able to find a rotor in good shape used on ebay with some form of guarantee? Sometimes you can get the whole front wheel assy cheap. I did.

[duaneage]

Rotor minimum thickness is stamped on the rotor. Grooved rotors are thinner than they measure. Minimum for most GS bikes are 4.5 mm on the front. Most I see are around 4.93 mm.

The rotor can be cleaned with 100 grit sandpaper on a block. Use swirling motion to create crosscut lines on the rotor. This will seat the pads better. Rotors are available cheap on ebay, you can get one delivered for around 15.00 sometimes.

[simon_C]

ive got a spare front rotor in pristine shape. want it?

[twistedwankel]

Rotor minimum thickness is stamped on the rotor. Grooved rotors are thinner than they measure. Minimum for most GS bikes are 4.5 mm on the front.

Duane...that is so good to know. I never noticed on the painted portion of both rotors it says: MIN. MM 4.5R and L I didn't know they came in right and left either. Lord I feel so smart now but it won't last.

You get the wise "owl" prize today:-D

Thanks for sharing. Doug