3EN2 17inch Rearwheel Mod - Help.

[Marb]

Ik have a 3EN2, and would like to convert it to 17inch. Now i have a complete 3TJ that i'm breaking so today i tore out the 3TJ swinger and my 3EN2 swinger to start fitting some parts.

What i discovered today.

1. The 3TJ swinger is too wide to slot into the 3EN2 frame 1 on 1. It's exactly as wide where the bearings are, but is quite a bit fatter so the swinger hits the rear-sets before you can get the bearing-rod thingy in.

2. The 3TJ swinger has a bigger bearing diameter. Which isn't such a big problem, different bearing wil do the trick.

3. The 3TJ 17inch wheel is a centimeter wider at the hub than the 3EN2 wheel. So the 3TJ wheel won't slot into the 3EN2 swinger without some mods.

My question is. How have people done this, if it has been done before. Use the entire rear-end, incl. swinger from the 3TJ or mod the wheel to fit in the 3EN2 swinger?

[Evilchicken0]

They don't, it's not worth the bother as the 17" rear messes with the handling the front wheels are different too. Just fit a sticky 18" tyre like an Alpha 10.

It's a bit different if you have a race bike where the tyres are more of a factor.

[Motorcycle Solutions]

Why not buy my frame and already slotted swing arm 3tj model but you will need to get 3tj engine to fit..

[uniquefzrfreak]

You need...

The 3TJ 17" wheel, obviously!
The 3TJ Sprocket Carrier

the 3EN2:

Axel
Sprocket
Chain
Caliper mount
Swingarm
Chain Adjusters

You will need to get 3mm machined off the sprocket carrier.
You will also a need bit of machined tube to shim down the wheel bearing holes, to take the 3EN2 axel. This (from some bog roll drawings I've got!) is about 121mm long, 20mm O/D, 17mm I/D
You will then need another bit of tube to shim down the 3TJ carrier whole. This one is something like 36mm long, 20mm O/D, 17mm I/D
You will need a new stepped top hat spacer making for the right hand side (between the caliper bracket and wheel). This is about 17mm long total, the right hand side of that 17mm (the last 3mm) needs to have an O/D of 30mm and an I/D of 17mm. The left side of the 17mm (basically the left 14mm's) needs an O/D of 25mm - I think - and an I/D of 17mm.
You will also need another small stepped washer on the left of the sprocket carrier that is about 5mm long. The right hand side of that 5mm (2mm of it) needs and I/D of 20mm, the left hand side (3mm of it) of that 5mm spacer, needs an I/D of 32mm and an O/D of 40mm.

I think that's the bulk of it (before I dumped it on a mate who'd measured it out and gave it his mate to machine for me. This will let you keep the 3EN2 spindle and maintain the chain alignment.

PM me your e-mail address for the rough measurements - if a little hard to read - my mate did me for my mod, after he did the same thing himself.

It works, although I put a 17 on the back to match up with the T/CAT 120 front wheel and forks I'm using. As stated, just chucking the 17" straight on an otherwise stock chassis for the road may cause worse handling.

[Taggyd]

i have it done on the race bike the pivot can be sorted by adding bushes to reduce it, the arm needs machining down to fit the width and the sprocket carrier was machined down by 3mm i think to align the sprockets properly but its was only worth it for racing as the tyre choices offered were better and i could get 2nd hand tyres cheap in 17"!!
on the road, wouldnt bother! the alpha tens are supposed to be really good!


EDIT! ^^^ beat me to it and a far better answer!!!! :D

[Marb]

Ok, thanks for the reply Unique.

But i was just wasn't sure on two things.

Which side did you machine down the sprocket carrier? The wheel side or the sprocket side?



Same for the brake-hanger, which side?



Got the rest sorted out. Just need to machine these two down and then it should all fit.

[uniquefzrfreak]

No worries, it's the sprocket side that you need to machine down. But it's the actual bits where the studs go in that the sprocket slots onto.

Simply remove the studs then take 3mm off each part surrounding each stud, so the sprocket sits 3mm closer to the center of the wheel than it does now, when it's bolted on.

- if you can tell me how to embed images in posts, I'll put and image of my sprocket carrier up -

You will then need to cut your studs down so they don't fowl on the inside of the swinging arm.

You don't need to machine down the caliper bracket at all.

Hope this helps.

[Marb]

If you host the pics on Photobucket and then put the link here between the [img] tags the pics should show up, or you can mail them to me (marb_i_am at hotmail dot com) and then i'll put them up here.

And thanks for the tips Unique!

Cheers, Bram

[Marb]

I can't seem to get it right. I machined down the 400RR wheel spacers and 3EN2 spacers according to Unique's spec but it doesnt seem to work.

The sprocket side spacer isnt wide enough, it results that the sprocket-carrier hits the swinger:



And the disk-side is too wide, so that i can't get the caliper hanger in between:



@Unique: Do you have any pics of yoursetup, just to get an idea how it all fits together. Cheers.

[uniquefzrfreak]

Well... please see the e-mail below I just sent Marb and the link to the images. I got the caliper bracket in after a fight, but generally ran into the same problem. See my cut and paste below and hopefully in a couple of days, I'll have the solution.

----

Please see this link for the images

http://www.derbyshirebikers.co.uk/forum/wheels/" onclick="window.open(this.href);return false;

Image 13 specifically shows the problem.

The good news is, that my mate is running this set up, I've seen it in action on his bike and he had the spacers made for me, I'd got the caliper bracket on the shelf for ages now as I was going to mod it to take an R1 rear caliper and so far assumed all was going to be as planned. However, I went out tonight to photo stuff for you and decided to drop the caliper bracket in to get a full fitted image, then.... I found exactly the same problem you have, I can't get the final thin spacer in on the left, no way... no how!

Admittedly, I'm using the standard 3EN2 sprocket carrier (less the sleeve that shims it down) as some bastard ripped me off and only after it was machined, did I find out it wasn't a 3TJ one. Other than the centre hole size though, they are identical.

I'll contact my mate with the images and get some advice over the next day or two, either way, we'll figure it out and I'm sure it won't be much.