R6 rear wheel fitment .

[cobbadiggabuddyblooo]

I also made up this 220mm set up but never ended up using it..

https://www.ebay.com.au/itm/182358006278

[pipsovich]

Seems gsxr caliper and mount is the easy way.
I made bushings and spacers to center the wheel in the frame. From sprocket Carrier bearing surface the bush protudes 7.5 mm. What is the best way to make sure the wheel is centered in the frame?

[cobbadiggabuddyblooo]

First you need to see if both the trx hub and the R6 hub are the same width and sit in the same spot in comparison to the rim.
It's best to unbolt the disc and sprocket
Use a straight edge on where the rear disc bolts on and measure to centre of rim on the std rim and then do the same on the R6 wheel.

Next fit the top hat spacer and do the same to find out how much extra to your centre of rim.
Use the first measurement for hub centres and keep the 2nd measurement with spacer Inplace for your centring in the swing arm later on.

Do the same on the sprocket side so you can get a total width of the hub and if there is any offset or extra width compared to the STD trx wheel.

Reason why it's best to unbolt the disc and sprocket as they may be different thicknesses.
Eg.. Std rear trx disc is about 5.5mm where as the 220mm disc I now have is only 4mm.
You can then work out your caliper carrier thickness and spacers as such to find out if your rim is central to the swing arm compared to the std trx measurement. You may need to alter either the top hat spacer to suit.

Get your wheel centred first , then work on sprocket alignment.
Good chance you can take material off the sprocket carrier or if the R6 uses an offset sprocket on the rear like the std TRX, you may be able to flip it around to find an extra couple of mm..

[pipsovich]

First you need to see if both the trx hub and the R6 hub are the same width and sit in the same spot in comparison to the rim.
It's best to unbolt the disc and sprocket
Use a straight edge on where the rear disc bolts on and measure to centre of rim on the std rim and then do the same on the R6 wheel.

Next fit the top hat spacer and do the same to find out how much extra to your centre of rim.
Use the first measurement for hub centres and keep the 2nd measurement with spacer Inplace for your centring in the swing arm later on.

Do the same on the sprocket side so you can get a total width of the hub and if there is any offset or extra width compared to the STD trx wheel.

Reason why it's best to unbolt the disc and sprocket as they may be different thicknesses.
Eg.. Std rear trx disc is about 5.5mm where as the 220mm disc I now have is only 4mm.
You can then work out your caliper carrier thickness and spacers as such to find out if your rim is central to the swing arm compared to the std trx measurement. You may need to alter either the top hat spacer to suit.

Get your wheel centred first , then work on sprocket alignment.
Good chance you can take material off the sprocket carrier or if the R6 uses an offset sprocket on the rear like the std TRX, you may be able to flip it around to find an extra couple of mm..

I used another method, with the std wheel mounted and tightened, i measured from the swingarm (on given points which i marked) to the edge of the rim in the bikes forward direction. I then used this measurement and put the R6 wheel in the same place. The distance from the rim edge to the edge of the swingarm is now the same as the std TRX wheel +/- 0,5mm. Is this an unsecure method? First i just measured the total width of the swingarm between axle holes and then centered the wheel to this measurement. But it seems that the wheel should be more to the left (sprocket) side in the swingarm to be centered to the frame.

[cobbadiggabuddyblooo]

If you work from the measurements from the wheel central axle point, the spacers & brake caliper bracket on the std trx wheel , then you know that will fit into the swingarm with wheels aligned and sprocket alignment.
That is a given and can be used as 0 reference points.
When you measure the R6 wheel you can find out if the R6 rim centre , hub alignment , sprocket and brake alignment are at your 0 reference point or if not, how much + or - from your 0 reference point from the std TRX wheel they are.

From there you can work out any wheel spacer / caliper mount differences you may need to make to get you to that 0 reference point again.

When setting this you can also get your caliper and disc centred at the same time because your brake caliper mount is a part of the wheel spacing.

Wheel alignment and brake sorted , you now look at how far the sprocket alignment will be out due to your 0 reference and look at options to get you there.

Measuring from the axle you are at centre of the wheel so there is less deviation + or - either by rim edge run out or mounting indifference.
That possible 1mm run out difference on your rim or just not getting the axle tightened in exactly the same spot can easily give you that 1 or 2 mm difference so then you take that out on you wheel centre at the axle spacing and your pushing your true wheel centre out by that measurement.

Hope this makes sense as measuring from the axle gives less room for + or - tollerence mistakes.


Cheers
Brian

[cobbadiggabuddyblooo]

GSXR 220mm rear caliper and mount.
The gsxr caliper mounting bracket is the same width at the axle as the std trx bracket.
It needs a bush inside to reduce the axle size to 20mm.
I just had to take 1-2mm from the caliper itself to get the caliper central to the disc.






This is the other 220mm rear brake set up I first started with mounted on top, but I then looked at bracing the swing arm so chose to go back to a caliper mounted underneath again.

[pipsovich]

I understand that if the wheel is a bit badly aligned, this will be worse as im measuring further away from the axle.
I find it hard to measure the distance of the bearing surface to the outer side of the rim in a reliable way.

REMOVED OLD MEASUREMENTS. See newer post for correct ones.

[cobbadiggabuddyblooo]

Cool bananas. The YZF750 rim was much the same as the R6 rim you have.
This shows the brake side of the hub is in the same position to the centre of the rim as the TRX and any extra rim width, by rights you should have your front and rear rim centres aligned.
If there's any extra width on the R6 hub, it should be on the sprocket side just like the YZF 750 5.5" rim..

Top job Pipsovich and thanks for sharing this...
Buy this man a beer for doing the hard yards and sharing it with us all.

If ever I built another TRX, I'd go down the R6 front end, R6 rear wheel option...
5 spoke looks so cool and lighter than the std TRX wheels.
You'll notice the difference straight away in the twisties. Tune you suspension accordingly and you'll quell any feeling of under steer with the wider 180 rear tyre.

You may find the reason the 1mm difference with the top hat may be because the actual trx wheel bearing width is 1mm different than the yzf/R6 wheel bearing. It's what I found with the YZF750 rim.

[pipsovich]

Cool bananas. The YZF750 rim was much the same as the R6 rim you have.
This shows the brake side of the hub is in the same position to the centre of the rim as the TRX and any extra rim width, by rights you should have your front and rear rim centres aligned.
If there's any extra width on the R6 hub, it should be on the sprocket side just like the YZF 750 5.5" rim..

Top job Pipsovich and thanks for sharing this...
Buy this man a beer for doing the hard yards and sharing it with us all.

If ever I built another TRX, I'd go down the R6 front end, R6 rear wheel option...
5 spoke looks so cool and lighter than the std TRX wheels.
You'll notice the difference straight away in the twisties. Tune you suspension accordingly and you'll quell any feeling of under steer with the wider 180 rear tyre.

You may find the reason the 1mm difference with the top hat may be because the actual trx wheel bearing width is 1mm different than the yzf/R6 wheel bearing. It's what I found with the YZF750 rim.

Ofcourse i share with you guys, but use this att your own risk
I couldn't help myself to measuring again today. This time i used calibrated, more suitable measuring tools that i borrowed.
These values are as good as i can get them.

ORG TRX WHEEL:
Rim total width: 145,6 mm
Distance bearing surface to rim edge: 19,5 mm
Org top hap bushing: 14,1 mm
Caliper mount: 27,0 mm
Distance from center of wheel to swingarm: 133,4 mm

2006 R6 5,5" WHEEL

Rim total width: 157,8 mm
Distance bearing surface to rim edge: -5,5 mm
My homemade top hat bushing: 13,0 mm
Caliper mount: 27,0 mm
A spacer 20,0 mm
Distance from center of wheel to swingarm: 133,4 mm


The top hat bushing on the drive side protrudes 7,0 mm from the bearing surface.
I can post simple drawings on all the bushings if anyone is interested. I sure would have been
And i will also post how i solve the aligning of sprockets issue.

[Ragnar]

...simple drawings on all the bushings if anyone is interested. I sure would have been ...

Im definitely interested!!! its needed to complete this topic, isnt it
And btw. good work!!

[pipsovich]

GSXR 220mm rear caliper and mount.
The gsxr caliper mounting bracket is the same width at the axle as the std trx bracket.
It needs a bush inside to reduce the axle size to 20mm.
I just had to take 1-2mm from the caliper itself to get the caliper central to the disc.






This is the other 220mm rear brake set up I first started with mounted on top, but I then looked at bracing the swing arm so chose to go back to a caliper mounted underneath again.

Im back building my bike again after buying house, moving and so on....

So i bought a gsxr caliper as you adviced. Problem is it does not fit a std r6 wheel. It interferes with the wheel itself. Have you tried it on a std wheel? The one on the pic looks a bit different.
Also do you still have the top mounted brake for sale?

[pipsovich]

What year did you take the caliper from? Mine looks a bit different actually.

[cobbadiggabuddyblooo]

Sold the top mounted 1 a couple of weeks ago.
2002 GSXR from memory on the gold caliper... I had to take a little material off the caliper itself where it mounts by 1-2mm to centre it on the disc.
The wheels I have are Dymags and built to run the std disc pattern / caliper mount so they may differ from the R6.
I just found a 220mm disc with the same TRX bolt pattern from a YZ hence the gsxr caliper mod...

[pipsovich]

Today i tested a 2002 caliper. It was the same. Does not fit. Any more bikes you know that runs a 220 rotor and under mounted caliper?

[cobbadiggabuddyblooo]

[/quote]

So i bought a gsxr caliper as you adviced. Problem is it does not fit a std r6 wheel. It interferes with the wheel itself. Have you tried it on a std wheel? The one on the pic looks a bit different.
Also do you still have the top mounted brake for sale? [/quote]

I originally was running the std TRX 245mm disc and caliper/mount on the Dymag wheel .
The wheel is built to suit the TRX with correct sprocket alignment and to use the std rear brake set up.
What about if you space the rear disc so it does not interfere with the R6 wheel and remove an equal amount of material from the caliper mount??