Straightening rotors/discs

[VWsurfbum]

I've got 220 Uber bike front rotor and it's always had a little squeak. It 'had' a tiny rub and I've tried straightening my normal way on the bike, then on the truing stand, I just can't get it right.

Anyone got any too tips on straightening before I go back to the Magura MDRP

 

[irie]

I have a sheet of absolutely "true" plate glass. If a rotor is slightly 'out' I put it on the plate glass and can immediately see where it's even slightly 'out'. Then adjust a very small bit at a time until it lies dead flat. Wearing nitrile gloves and an immaculately clean surface on the plate glass of course. Works for me, but don't have floating rotors.

 

[VWsurfbum]

I have a sheet of absolutely "true" plate glass. If a rotor is slightly 'out' I put it on the plate glass and can immediately see where it's even slightly 'out'. Then adjust a very small bit at a time until it lies dead flat. Wearing nitrile gloves and an immaculately clean surface on the plate glass of course. Works for me.

How are you adjusting?

 

[irie]

How are you adjusting?

Using a Rotor Truing Fork, mine is Park Tool DT-2, but there are much cheaper ones which I am sure also work OK.

 

[VWsurfbum]

Using a Rotor Truing Fork, mine is Park Tool DT-2, but there are much cheaper ones which I am sure also work OK.

Cheers

 

[arTNC]

Using a Rotor Truing Fork, mine is Park Tool DT-2, but there are much cheaper ones which I am sure also work OK.

Yep, great tool. The truing effort "can" be done with the rotor on the wheel being very patient and using the caliper/pads as a guide...depending on how bad the tweak is. If done off the hub, it helps to have two of those tools.

 

[RustyMTB]

I use an adjustable spanner, the sort of thing plumbers have. Works a treat.

 

[jetskier973]

I recently trued one my rotors with only the bare wheel on the bike.
Without the additional rotating mass of the tire and insert, it was easy to pinpoint the spots on the rotor that needed attention by gently spinning the wheel and letting it stop accurately on those spots.
After the tire was back on, the wheel/tire combo spun much more freely.
I was amazed and happy, and I couldn't believe what I thought was good enough beforehand.

Working with Magura MDR-P 220mm rotors.

 

[irie]

I use an adjustable spanner, the sort of thing plumbers have. Works a treat.

That's what I used before getting the 'truer'.

 

[VWsurfbum]

I own lots of very specific tools, I've always avoided owning an adjustable spanner lol. But it might be easier to obtain quickly than a disc fork tool.

 

[RustyMTB]

Nice tools are nice but it's also true an adjustable spanner & truing tool work in exactly the same way Either will work ok. As an observation, truing discs is one of the more tedious jobs on a bike. It's a bit at a time for ever & ever until the damn thing starightens out. Pro tip, find the bent section & mark it with a sharpie, saves you bending the wrong bit & making it worse.

 

[Binhill1]

I've got 220 Uber bike front rotor and it's always had a little squeak. It 'had' a tiny rub and I've tried straightening my normal way on the bike, then on the truing stand, I just can't get it right.

Anyone got any too tips on straightening before I go back to the Magura MDRP

Couple of shifters I've used and been ok. Depending how bad it is or how precise you want it to be.

 

[VWsurfbum]

Well i made it have more high points, so I ordered a set of new rotors.

 

[irie]

Well i made it have more high points, so I ordered a set of new rotors.

In the same vein, had a 20mm strip of Gorilla tape on top of the Invisiframe on the lower edge on my Rail battery and on yesterday's ride in rough-as-fuck stuff slightly lifted one end of the Gorilla tape. Thought, I'll just lift that off and put another piece of Gorilla tape on. In doing so lifted the fucking Invisiframe.

So off today to a local company that hopefully has some stock to buy a small sheet and reapply it on the battery.

Got to change the chain and clean wife's transmission (on her bike that is ) so that's my day sorted.

 

[kombos]

My free truing tool is a short scrap of aluminum bar with a slot cut in it….