Front brake rotors are swappable?

[quant55]

I don't know if that has been asked before, but, for a VR90 are the front brake rotors swappable? I mean keeping the correct cooling air flow? From pictures I've seen on the net they look to be, but anyone has hands on experience with that? I know there are different part numbers for the two rotors...

 

Also, what is the minimum acceptable thickness of the rotor? My right rotor is about 6.1mm and the left is about 6.5mm. I just found at a seller a used LEFT rotor that is about 7.0mm and I wonder if it can be a replacement for my RIGHT rotor.

 

Regards,

Corneliu

[sleepy2]

I have an 87VR and years ago I swapped out my worn out right(I am told it wears out more because linked front left to rear rotors and I used front brake more)) with a used left one from another bike. All you have to do is put it on with the cooling fins pointing(rotating) the same way.So if you take left one off put on right side the same way(fins will be same way.There is a slight thickness on the ridge in center but this does not(at least on mine) make brakes work any different.

Not sure about thickness of rotors BUT if you have repair manual it will be in there--if no book look on site as it was posted before that you could download a manual.

Hope this helps!

[dingy]

The rotors you are looking at on ebay will work fine on your bike, rotor can be moved from left to right (or other way) as long as cutouts are oriented the same. This means a normal right rotor's face that is bolted against the rim, when moved to the left side will now have the opposite side bolted up to the rim.

 

Something to consider, it depends on what is used to measure a rotor that will determine the actual wear on the rotor. Brake pads do not come all the way to the edge of a rotor, they stop about a 1/16" shy of the edge. This then means that the very outer edge never gets worn down. If a standard set of calipers are used to measure the thickness, there is a good possibility that the outer edge will be measured and not the wearing surface. Not sure if this is a valid concern since the rotor measured differently. But new specs on a 90 rotor is 7.0 thick, and this one is measured at 7.0 thick.

 

Below are the ebay item numbers for the left & right calipers from what I think is the same bike. The left pads look new, the right set is almost gone. Somewhat typical of what I would expect wear wise from an experienced rider using a linked brake setup.

 

This bike has 47,000 miles on it. The left rotor looks grooved somewhat as compared to the right, but this can be deceiving in photos. Again, though, what I would expect from linked brakes with an experienced rider. reason is the left is used far less than the right rotor. This allows road debris to slightly accumulate more on the less used left rotor, then when it is used, this ever so slight build up wears more on the rotor face. Reason I think this does not happen as much on the right is it is used much more often and build up is minimal when brakes are used at a higher frequency.

 

There is a specialized micrometer that is used to measure rotors that has a point on the face of the rotor and reaches past the outer ridge.

 

330712642078 Left caliper

 

350555150922 Right caliper

 

For $56.50 each, they look like a very nice set.

 

Gary

[quant55]

I have an 87VR and years ago I swapped out my worn out right(I am told it wears out more because linked front left to rear rotors and I used front brake more)) with a used left one from another bike. All you have to do is put it on with the cooling fins pointing(rotating) the same way.So if you take left one off put on right side the same way(fins will be same way.There is a slight thickness on the ridge in center but this does not(at least on mine) make brakes work any different.

Not sure about thickness of rotors BUT if you have repair manual it will be in there--if no book look on site as it was posted before that you could download a manual.

Hope this helps!

 

I found the manual: minimum thickness is as follows:

Front rotor: 6.5mm

Rear rotor: 4.5mm

 

My right brake rotor then have to be replaced...

 

Regards,

Corneliu

[quant55]

The rotors you are looking at on ebay will work fine on your bike, rotor can be moved from left to right (or other way) as long as cutouts are oriented the same. This means a normal right rotor's face that is bolted against the rim, when moved to the left side will now have the opposite side bolted up to the rim.

 

 

330712642078 Left caliper

 

350555150922 Right caliper

 

For $56.50 each, they look like a very nice set.

 

Gary

 

Gary, those are exactly the items I was looking for on ebay. I'm thinking either to go with the left rotor (+ left caliper as a spare) or to go for new after market rotors. Looking around on ebay, I found some offers between ~$120 and $150 for a pair of new brake disks (they say for VR 84-87...). What do you think it worth the most? Just to replace the left disk with that used, but almost new OEM disk or to go to some aftermarket new disks?

 

Corneliu

[dingy]

I found some offers between ~$120 and $150 for a pair of new brake disks (they say for VR 84-87...). What do you think it worth the most? Just to replace the left disk with that used, but almost new OEM disk or to go to some aftermarket new disks?

 

Corneliu

Post an item number for the aftermarket ones you are looking at.

 

There are a lot of 'Wave" rotors out there. Most of these a 5mm thick, which would cause the caliper not to be centered over the centerlin of the rotor. Not sure if this is a critical problem but it will cause the outboard pistons to be extended farther out of the caliper by 2.5mm (.098"). Not sure if this is getting close to allow caliper to pass seal when pad is at its wear minimum or not.

 

Also, 84 & 85 rotors are different from 86 & 87. I messaged this guy about that some time ago & he keeps listing them like this. 83~85 are 298 dia & 86~93 are 282 dia on the fronts.

 

Gary

Edited May 12, 2012 by dingy

[quant55]

Gary, Thanks, you're right, I'm going to that used 7.0mm rotor.

[quant55]

Thank you for your answers. I already replaced the front right rotor with a left rotor taken from another bike and the offset on the mounting flange is insignificant, just about 0.25-0.30mm. The front brake now really works well, so the answer is really yes, the rotors are swappable (I own a VR90).