Rear wheels on the front, and disc converters

[quallman1234]

At the moment, i am wanting to put a 17" front rim on my bucket. As the stock rim is a 16" and isn't very fun finding cheap sticky tires for it.

My rear rim is a 2.75x17" so thats okay. I have sitting around (thanks to hamish), a 2.15x17" of a FXR150 rear.
I was thinking of putting the 2.15 of the FXR rear on to the front of my bucket. But the original disc on this rim is obviously too small to be all the efficient.

I was thinking of using the disc off the 16" rim on the FXR rear. Because the size is larger, and also the caliper height would be the same.
The problem is the FXR rear has a 4 bolt disc, where as the disc i want too use has a 6 bolt hole. Therefore a disc converter needs to be fabricated. I have already checked if there is enough room between the forks and there is plenty.

First question is, is there anything wrong with using a rear rim on the front?

The second question is, what is the best way of making a disc converter.
I would think it needs to be quite accurate. What thickness should i use?

I did make a prototype one on some 3mm steel. By punching a center, measuring with a metal compass too the right diameter of where the holes are with respect to the center of the disc for both disc's. Then lined up the disc holes made a small crater roughly where the hole center should be for a starting point, and used the compass to find the rest. This worked okay, but not sure if it would be accurate enough.

I was thinking maybe i should turn down some steel on the lathe, and mark the the diameter of were it should go then, drill one hole and bolt the disc on and drill the others. For each disc.

Any other ideas?

Thanks Heaps
-Kyle

[bucketracer]

The problem is the FXR rear has a 4 bolt disc, where as the disc i want too use has a 6 bolt hole.


Its Ok to use a rear rim on the front. When marking out the bolt holes, you may remember from school maths/tech drawing that the radius divides into the circumference six times. Handy for marking out six bolt holes.

I mark out the circles circumference then put a center pop on the line and divide of three bolt holes one way then three the other. Opposite the center pop you should have two lines very close together.

Center pop in the middle between them, and divide of three bolt holes one way then three the other from the new center pop.

You should now have four sets of lines close together and two straddling the original center pop. Center pop between the four sets of new lines and you will have an accurately marked out circle with six evenly spaced center pops ready for drilling.

[nudemetalz]

Well, I went the other way and used a front wheel on the rear (in this case a 3" x 17"). That works fine.
I mean to say, I got a DT175 rear sprocket to perfectly line up with the disc mounting holes of the rim without any mods required.
So, what I would do is look at other discs to see if they will be better for fitting to your rim.

Anything is possible.
Remember it's bucket racing, ie experimentation to the extreme !!!

[Sidewinder]

its a bucket so its meant to be maori boy racing, go for gold man

[quallman1234]

Pretty hard too find a decent sized disc for a 4 hole alignment. I figured i should use my orignal disc so i dont have to bugger around making calipers mounts too much =).

Ive got something figured out anyway! Only a little bit worried about weight. As a piece of 8mm thick steel is going to be putting the wheel out of balance pretty easily. I need some ally. But i get steel for free :clap:

[DELLORTO]

Pretty hard too find a decent sized disc for a 4 hole alignment. I figured i should use my orignal disc so i dont have to bugger around making calipers mounts too much =).

Ive got something figured out anyway! Only a little bit worried about weight. As a piece of 8mm thick steel is going to be putting the wheel out of balance pretty easily. I need some ally. But i get steel for free :clap:

hae wat sort of bucket do you have anyway??

[quallman1234]

Its a bitsa.

Aprilla RS50 with a TF125 Engine in it. Singe Sided Swingarm Brembo brakes. Etc Sounds fancy but its a piece of shit. My doing.

[andrew a]

Hi Kyle I have an FXR rear wheel on the front of the bike now. The axle size was a problem but made spacers with diferent bearings. I fitted the FXR front disk by making an alloy spacer. The spacer started life as a shiney car wheel. It took hours to machen down. First ride was the slipway and seamed OK. Kaitoki will be the test.

[quallman1234]

Hi Kyle I have an FXR rear wheel on the front of the bike now. The axle size was a problem but made spacers with diferent bearings. I fitted the FXR front disk by making an alloy spacer. The spacer started life as a shiney car wheel. It took hours to machen down. First ride was the slipway and seamed OK. Kaitoki will be the test.

Sweet as. Haha thats an interesting way of using whatever's around you. I'm going to get a piece of 10mm plate plasma cut out today. And then turn it down to suit tonight. Make a sleeve for the disc too fit over so i can just use the drill piece to find the holes. Shouldn't really be too big of a deal. Weight should be okay. If its crap ill make one out of some ally if i can get some. Or find something to use.

Cheers

[jasonu]

10mm steel??? Way to heavy. Use aluminium.

[Sketchy_Racer]

Haha, give it a shot with the steel Kyle, but I think your front wheel may become one hell of a boat anchor.....

[bucketracer]

Drill lots of lightning holes in it, its amazing how much weight can be taken out with a few holes.

[gav]

My FXR actually has the std FXR rear rim but has a 2.50 x 17 front rim, so the front is wider than the rear. I use the same size 90/65 17" slicks front and rear, seems OK. Even Bren who rode it was impressed, in theory it shouldnt handle as good as it does, but all seems to work. :yes:

[quallman1234]

Haha, give it a shot with the steel Kyle, but I think your front wheel may become one hell of a boat anchor.....

Yea ill give it a go with some steel first so i don't waste some ally. Might as well try drill some holes in after too loose some weight.

I was thinking 125 front Slicks both ends, thanks gav! But will see as i only have 1 front and 1 rear. But shouldn't be hard to get some more.

[F5 Dave]

on my 50 at I had 2.5s both front & rear & I had a Dunlop & a Bridgestone. at the time ~2000 the dunlops were considerably sharper profile than the rounded Bridgey so I ran the 'lop on the front despite being a 95 to the rear's 90. Worked fine but man did it tip in super fast!@

[quallman1234]

After much procrastination i finally made one months later.

[Sketchy_Racer]

Good work Kyle, now we wait to see the rest of the bike come together! ;)

[marsheng]

One thing you have to be sure of is the faces have to be parallel, else the disk will have wobble.

If you send the sizes, I can CNC the adapter plate.

Cheers Wallace

[Damien_Toman]

My FXR actually has the std FXR rear rim but has a 2.50 x 17 front rim, so the front is wider than the rear. I use the same size 90/65 17" slicks front and rear, seems OK. Even Bren who rode it was impressed, in theory it shouldnt handle as good as it does, but all seems to work. :yes:

Now that is very interesting! Any more info/pics?

[quallman1234]

Good work Kyle, now we wait to see the rest of the bike come together! ;)

Don't be silly! :stupid:.

It might happen one day. =P.