Swingarms

[olddogs]

Hey group. I have a reed valve Combat Wombat engine in an 03 frame I use for the non-current motocross class. I have T-DOG rear shocks and forks on it. I love the way it handles the jumps and chop. I have a Super Combat I use in the Vintage Ironman class with T-DOG forks and 14 and a half inch Works rear shocks. The extra wheelbase on the 03 setup seems to make for a much better handling bike. Has anyone tried putting the longer 03 swing arm on a SC frame? Does it fit? Are there insurmountable wheel and chain alignment problems? The 2 frames have slightly different rakes, but I think its the swing arm making the difference.

[thirdstone]

I have a longer swing arm on a 94 frame and it improved the handleing a lot.

[hodakaguy]

Hey group. I have a reed valve Combat Wombat engine in an 03 frame I use for the non-current motocross class. I have T-DOG rear shocks and forks on it. I love the way it handles the jumps and chop. I have a Super Combat I use in the Vintage Ironman class with T-DOG forks and 14 and a half inch Works rear shocks. The extra wheelbase on the 03 setup seems to make for a much better handling bike. Has anyone tried putting the longer 03 swing arm on a SC frame? Does it fit? Are there insurmountable wheel and chain alignment problems? The 2 frames have slightly different rakes, but I think its the swing arm making the difference.

I just went to the shop and looked at 3 swingarms. The 03, Super Rat 98 and road toad. All 3 are exactly identical in length. Is there a 03 swingarm I am not aware of that is longer?

[olddogs]

Thanks for looking. The 03 swingarm is about an inch and a half longer. You can tell by the extra length of the 03 swingarm tube between the lower shock mount and axle slot. The distance between the swingarm pivot bolt and shock mount are the same, the extra length is after the shock. I have 2 03 wombats and both have swingarms that measure 20 inches from pivot center to the end of the swingarm. The Toad and SC are 18 and a half inches from pivot center to the end of the axle slot. I found a used 03 swingarm and am going to experiment. I will post the results in case anyone else is interested.

[BrianZ]

I have what I believe is a 175SL swingarm on my Super Combat. The longer swingarm improved the handling. The swingarm fit with no major modifications. I did have to make up a new rear pipe stay and make up spacers for the shock mounts. An added benefit is that the left rear shock can be spaced further from the rear chain.

Brian

[socalhodaka]

We ran the 03 arm on a back up bike and you need all the correct spacers from the 03 to make it work.

[olddogs]

Thanks for the info. Looks like a Road Toad sprocket carrier and some older model spacers are all that are needed. I was worried about it even fitting.

[eichco1]

I have a 03 swing arm on my late 97. I would use the 97 sprocket carrier. The stock wheel is a bolt on. The left shock will need at least the 03 bottom spacer and bolt. The top bolt depends on what shocks you use. You will also need the longer brake rod and brake stay. The other concerns are the chain guard and chain guide. The 03 motor is offset to the left about 6mm for the oil injection and primary kick. So these items won't line up properly with the chain without some modifications.

The early 97 used a "distance collar", and "center collar". I would think these would need to be installed in the 03 arm for proper operation on a early 97. The late 97's used a clamp on the swing arm bolt like the 98/99/01/02/03.

Mark in Illinois
#492

[eichco1]

Hodakaguy, it sounds like someone swapped out a 99/01/02 arm on your 03. If you post a picture we could tell you if that is so.

BrianZ, I would like to see a pic of your 175 arm on your 97 as well. Sounds trick!

As far as I can remember, the 03 arm is 1 1/8" longer. The rear shock mount on the arm is moved forward about 3/8" to pick up the back end for the longer 34mm forks on the 03. These numbers might be off though. I'm digging my 97 out tomorrow. I'll try to post a pic of the arm.

Mark in Illinois
#492

[hodakaguy]

Looks like case closed. I have a Super Combat swingarm and not a 03. The swingarm bolt is thinner and has grease nipples on both ends. This is only on the Super Combat as far as I can see.

[eichco1]

This is an 03 arm on a late 97 frame.

[eichco1]

Sorry for the delay in posting the pic.
I rode a Midwest VMX event on Sunday at MCMotopark, which is basically a modern track tamed down a little.
http://www.mcmotopark.com/
I am still hobbling a bit.

I pulled the other bike in my class out of the hole both motos, a 74 KX 125, but faded after that.

Favorite quote of the day as I was pulling in with my 97 on the trailer by a youngster, "he's gonna ride that thing?"

Mark in Illinois
#492

[hodakaguy]

Thanks for the pic. I looked closer and I seem to have a 1972 wombat swngarm with a Super Comgat swingarm bolt (has grease nipples and nuts on both ends)

[olddogs]

The 03 swing arm arrived and was a indeed a direct bolt on to the 97SC frame. I did need to use the distance spacer from the inside of the 97 swing arm to hold the bushings in the right spot. The chain and sprocket were right in line the countershaft sprocket. I did need the longer lower shock bolt from an 03 and just moved the spacer the 03 used to clear the shock body away from the chain, to the outside. No spacer was then needed on the top, the 97 upper shock bolt worked. I also needed a longer chain to make up for the longer swing arm. The lower chain guide was shimmed over, and a new chain roller was welded near the front of the swing arm. The back of the rear fender is now a little closer to the tire, but if it doesn't rub this weekend, it will probably stay where it is. All in all it was a fun project. The next race will tell me if it was worth the effort.