Fork stem issue

[NordieBoy]

I'm re-forking a 1981 GSX400F and can use either a pair of shortened KX125 USD's or DR650 forks.

I'd rather use the DR's forks and keep it Suzuki but...

The KX125 stem is 30mm at the bottom bearing and 25mm at the top.
The top bearing surface needs lowering by 5mm or so and it'd fit perfectly.

The DR650 stem is 30mm at the bottom and 30mm at the top.

The KX bearing will fit on the DR stem for the bottom
They can't find me a bearing to fit the DR stem in the top

The DR and KX wheels both use the same axle diameter so with some fiddling (spacers and caliper re-positioning) the DR wheel would work with the KX forks.

The KX sliders are 39mm.
The DR sliders are 43mm.

To use the DR stem it'd need the top bearing surface machined down to 25mm diameter and the top clamp bit down to about 20mm.
Catch is, it's hollow so I'm not sure about the 20mm bit.

Anyone pressed out a DR stem or know how they're fitted?
Then I could go KX stem in DR clamps?

If I machine the DR stem I can sell the KX front end complete and it pays for the machining.


Aaarrrggghhh...

[F5 Dave]

I briefly skimmed this, but I can't get past why anyone is doing anything with a GSX400 four.

[NordieBoy]

I briefly skimmed this, but I can't get past why anyone is doing anything with a GSX400 four.

This is why...

[T.W.R]

This the inspiration ?

http://www.trademe.co.nz/Trade-Me-Mo...-295357254.htm

[NordieBoy]

This the inspiration ?

http://www.trademe.co.nz/Trade-Me-Mo...-295357254.htm

Nah. This one...

[T.W.R]

Timken do a bearing that'd suit the KX stem to fit the DR dimensions (30x52x16) ; Timken # TRB 30205 (25x52x16.25)

Same with NSK, their bearing is # HR30205C

[NordieBoy]

The GSX stem hole is 47mm on the top and 56mm on the bottom.

Top bearing to suit the KX stem would be 25x47
Bottom bearing for the KX would be 30x56

Top bearing to suit the DR stem would be 30x47 - not enough room for the shells and races to fit in there.
Bottom bearing for the DR would be 30x56

Bottom bearing is no problem.
KX top bearing is no problem.

Looks like the KX stem in the DR clamps is the go.
The top bearing surface just needs to be extended downward 5mm or so and the DR top clamp just needs a sleeve to take it from 30mm down to 25mm.

Pressing the stems out.
You'd press from the top? Assuming they're pressed in from the bottom?

[T.W.R]

So you need suzuki part #09265-25019 bearing: RT 25x47x15 BRG

US price $33.97

pretty sure it'd be press out from the bottom

[NordieBoy]

So you need suzuki part #09265-25019 bearing: RT 25x47x15 BRG

US price $33.97

Yep - $20 from SKF. They've even got them on the shelf here

pretty sure it'd be press out from the bottom

We tried that with 2,000kpa but no movement but also no idea of how much it would take to get movement.

[NordieBoy]

Press out from the top - toward the wheel.

The KX stem is in the DR bottom clamp.

The bottom of the KX stem was a fraction of a gnats whisker smaller than the DR one so is held in by the spring clip and the bearing.

Sweet

[SS90]

This is why...

You know, that is actually pretty cool...it's not the sort of thing that I would build for myself, but I think it's cool!

[NordieBoy]

Thanks

At the moment apart from the front end, if you look at it too hard it'd fall apart. Everything is just sitting together.

[imdying]

You know, that is actually pretty cool...it's not the sort of thing that I would build for myself, but I think it's cool!

Same here... It would probably eat me given my dirt experience, but still very cool!

[eelracing]

Any chance you would be entering this in the next Nth v Sth VMX round per chance eh?

Jeez you bloody southerners and ya 4 strokes will do anything to beat a northern twotanger.

I must admit she will be a looker when done,if a bit wobbly in the rough tho haha.

[NordieBoy]

Any chance you would be entering this in the next Nth v Sth VMX round per chance eh?

Jeez you bloody southerners and ya 4 strokes will do anything to beat a northern twotanger.

I must admit she will be a looker when done,if a bit wobbly in the rough tho haha.

Bloody mud islanders. Having to resort to smokers to beat mainlanders on proper bikes.

Disc brakes - vmx?

Only Suzuki could mix technologies soo badly. Damper rod forks and 290mm disc

Nothing I'm doing here is out of place really...

Wobbly? It'll be doing at least 1 laid back trail ride when it gets going. Also maybe at least 1 beach race too...