fork interchange

[Bailey28]

Anyone know if WP 48mm open chamber forks will interchange with the Sachs forks as far as clamp diameter goes?

I have a revalved set of 48mm's I'd like to try. I would have to use the KTM front wheel on the GG as well. The brake rotors are the same diameter as well as the caliper mount.

Side by side on each bike both the Sachs and the WP outer tubes look like they are the exact same diameter and length. They even have the same machine work and the same "step" down and parts by the fork seal area. Does the same company make both the Sachs and the WP fork tubes?

 

[roostafish]

If You have both sitting there, try the swap. Let us know.

 

[GMP]

Just get a caliper and measure them.

 

[Bailey28]

I still have to take both bikes apart. I looked at it again and the upper WP legs will fit into the GG clamps. The forks are the same length top to bottom.

The only thing that is different is the axle, the KTM has a 26mm front axle and the GG is a bit smaller. I can run the KTM wheel with the setup as the rotors are the same diameter.

It looks like the axle offset is the same also. I know any change here no matter how small can make a big difference in the way the bike handles.

Sorry for the strip tease, I just started looking at this last night at 11pm. I will try to get into the garage tonight and do a quick swap for sure. I'm at work now so its a no go until later.

 

[Bailey28]

I still have to take both bikes apart. I looked at it again and the upper WP legs will fit into the GG clamps. The forks are the same length top to bottom.

The only thing that is different is the axle, the KTM has a 26mm front axle and the GG is a bit smaller. I can run the KTM wheel with the setup as the rotors are the same diameter. I cannot swap rotors because the mounting bolts are spaced different.

It looks like the axle offset is the same also. I know any change here no matter how small can make a big difference in the way the bike handles.

I wanted to try this as my WP legs were revalved by EE and they are super plush. The only complaint about the Sachs legs I have as of now with 5 hours on the bike is that they are very harsh entering a corner with braking bumps. It feels like the bike disconnects from the ground. I will try speeding the rebound up in case they are packing but from what you guys are saying i need to have them revalved.

 

[GMP]

You don't need to take anything apart to measure the top and bottom claming dias. Put a caliper on the tube at the top edge of the lower clamp and lower edge of the top clamp. Axel offset the same is good, but you have to measure it carefully. GG clamps are 21mm offset, which undoubtably contributes to the good steering. I considered a complete Honda/Showa swap but then your back to 22-24mm offset clamps unless you buy aftermarket then it gets too pricey, plus they still have to me modified.

Just to try it the KTM wheel would be the easiest way. To use the GG wheel you could have an axel and spacers made. I would do this as I have a couple spare GG wheels on hand.

I wouldn't judge the Sachs with the stock valving.

 

[Bailey28]

Yeah I think I will wait until I get more time on the Sachs stuff before I make any judgements about the vavling. Funny thing is, I love the rear shock, and the forks everywhere except for braking stutter bumps. The faster I ride the better they get even on an MX track.

I was not going to change the upper or lower triple clamps if that what you meant by "offset" however the axle offset, or where the center of the axle is in relation to the center of the lower fork tube. They "look" the same.

Out to the garage now.... Oh, I can imagine how good the GG can feel, even more so than with the Sachs. The '10 demo 300 I rode at Kirt's shop had Don Learn's Ohlins personal setup on them. It was MAGIC. I am spoiled and wish I didn't ride the darn thing. I can't affor Ohlins.....

 

[GMP]

What I meant was don't judge the Sachs quality by the stock valving. I never buy a new bike and expect the stock valving to work for me.

 

[Bailey28]

Darn it, I didn't get my forks done however I just installed a set of Ti pegs from a Yamaha 450. They sit 1/4" more toward the front of the bike and weigh 3.5 oz less per peg. So for $35.00 I shaved 7 oz off the bike.

The KTM valving did not work for me either when I got that bike new. EE revalved it and they are great for me now. They may be a bit stiff going from a 249lb bike onto a 224 lb bike, but nothing that letting the clickers out a little wouldn't solve. The WP's from the KTM have .42's in them already with 0 preload on them, no preload spacers in them, and set up for woods.

The Sachs now actually feel very similar to how the WP's felt before I got them revalved. They were also a tad harsh in the midstroke, and they didn't like small closely spaced braking bumps.

I am also glad to see another NJ guy on here, I am originally from Sayreville NJ, (Middlesex county).

 

[ScottyR]

Get EE to revalve your Sachs forks. Al Randt owns a 2011 EC300 with Sachs and he told me personally that he is very happy with the suspension now that it has been massaged.

 

[Bailey28]

Dave Kyle at EE revalved my KTM stuff and I was very happy with the shock and forks on that bike. It is just that the GG surpasses the KTM in every way so the Katoom is for sale now. On my buddy's track, I am 10 seconds faster a lap on the GG. 10 SECONDS. AS IS. FROM THE FACTORY. WITH NO SUSPENSION MODS YET. To me that is almost unbelievable.

 

[GMP]

4-stroke valving tends to be different due to compression braking and weight bias, not just weight. I don't think the WPs woul'd feel as good just slapped on the GG.