Tired Combat Wombat

[dcooke007]

Can't seem to let this go so another attempt today.....obsessive???? Nah.... just curious minds want to know......that's my story and I am sticking to it. So took a different approach. I had to swap the rear sprocket any way and while I had the sprockets off I measured sprocket mount off set on the two carriers. There is 5mm difference between the one on the bike and my spare 03 carrier. This is what I would expect to find on the early verses late Hodaka 125 carriers. Also removed the rear tire, loosened the spokes and trued the rim. Chased down my T square and used the long part to better check sprocket alignment.

My thoughts were to make a spacer for the sprocket side of the wheel that matches the off set of the 03 Wombat sprocket carrier......5mm.

Attempted to remove 5mm from the brake side wheel spacer to compensate for the 5mm added to the sprocket side. Although I made the sprocket side spacer exactly at 5mm I missed the mark a little on the brake side spacer. Original length was 28.97mm and should have been shortened to 23.97mm.....I think this will do though.

Installed the wheel with the 03 sprocket carrier, fabricated spacers and using a cross test level I checked plumb on the front and rear sprocket. This assists in checking for frame twist and making sure both sprockets are in the same plane. Ended up with half bubble off and I think that is reasonably close enough for production tolerances.

Checked wheel alignment with string....again. Centered up nicely.

Using the T square part I can check sprocket alignment more precisely. Sprockets are aligned within .010 inch and that is good enough.

Fabricated spacers installed.

In the end re-centering and trueing the rear rim, using the 03 Wombat sprocket carrier and spacing the wheel 5mm to the right put every thing in alignment. I looked at the wheel hub and it looks the same as my spare 03 Wombat. This mis-match of parts would explain this issue. I do not have a Combat Wombat wheel hub to compare.

Danny

[dcooke007]

Ed pointed out some areas he thought might be bent. So with his input I checked those areas. One area did indeed prove bent.

Placed a level on the forward part of the frame loop.

Placed the level on the rear part of the loop and you can see the bend. Probably took a tumble at some point. Even though it is bent it is not causing any other mis-alignment. I am going to see if I can straighten it but if not it will probably only affect the seat slightly.

Danny

[hodakamax]

Good job Danny, you seem to be on top of everything, keep up the good work, I enjoy your posts.

Max

[dcooke007]

Thanks Max. A bit of a challenge but I think the worst part is over. The front wheel and forks need a little more refinement also but not like the rear. Still have to wire the lights too. Can't wait to finally get this thing sorted out and take it for a spin.

Danny

[dcooke007]

Made a little more progress today. Cleaned the spark arrestor but not enough time to clean the pipe. Pipe looks ok inside so keeping fingers crossed at this time. Worked on the lighting wiring, air filter and exhaust.

Danny

[hodakamax]

Just finished looking at the pictures and blowing them up. The project is looking good especially that engine! Cheez! we just got out of the tornado shelter! We're OK and no damage. We are in Kansas you know. Anyway, Keep up the good work! Later--

Maxie

[dcooke007]

Max, hope every thing is ok. Say hello to Dorothy for me....sorry could not help myself.

Danny

[hodakamax]

I was trying to work that Oz thing in but I thought it to be too corny, so to speak! Holy Moley! just this minute we got the word that it's time to take shelter again! We have a bullet proof saferoom, we'll be OK! I might report back later GOTTA GO!

[hodakamax]

Looks like we're OK again-- looks like it went south of us. Exciting Huh! Just life in Kansas. Looking forward to more posts, keep up the good work!

Maxie

[hodakamax]

Hey Danny--Thought I'd finish my crazy weather report from last night even though it's not Hodaka related. Alert at 2:30 AM, back to the shelter and soon all clear. I was really awake by then so I checked the Forum one more time but everyone was asleep!--Reporting from Kansas as always-----

Maxie

[dcooke007]

Lots of little things on this bike that need attention and consume time to figure out a fix. The air filter stud was broken off and I should have caught it before installing the housing. Stuffed a paper towel in the air boot and trimmed the broken stud down. Drilled the remainder of the stud and tapped the hole 6mm x 1.0. Used an old engine side cover screw to make a new stud. Installed the stud and installed jam nut. A healthy dose of red Loctite was applied to all those parts. The last thing you want to happen would be for any loose parts to go in the engine. New air filter oiled, gasket fabricated and air filter completed.

Danny

[dcooke007]

After sorting out the air filter, sourcing the springs and hardware to secure the exhaust and add trans oil it was time to start this puppy. Engine started on the second kick. Warmed it up and set the idle mixture.

I only have the headlamp and tail lamp circuit completed. There is no headlamp switch or brake lamp switch / wiring installed and may not be completed before the racing season begins. The headlamp and tail lamp simply turn on with the engine running at this point. I am using a single lighting coil and the lights dim slightly at idle. Lamp out put is bright just above idle rpm.

The wiring is fairly simple. The Combat Wombat usually has only two wires blue and black. As you can see I added a green 18 guage wire for the lighting output circuit. The green wire comes from the lighting coil to the voltage regulator and then supplies power to the associated lights or switches. The blue wire is the stator ground wire that goes to the coil. The blue coil wire has a double connector and I added another circuit to this connector for direct ground to the coil core, frame and engine. This should maintain a good ground even if a poor ground condition develops at the engine mounts.

Six volt 03 Wombat voltage regulator. I did not run a ground circuit for the lights. Simply grounded the lights through the frame and coated with liquid tape to protect the connection.

Danny

[dcooke007]

A lot more accomplished today. Found a mdl 94 horn / dimmer switch to use as a headlamp on / off switch. Soaked the switch in Evapo-rust and dis assembled. Removed the black horn ground wire and the yellow headlamp dimmer wire. That left the brown and light blue wire. With these two wires I had a functioning headlamp switch. Mounted the rear tire and installed. Cable tied the wiring and mounted the tank and seat.

Poured in some pre-mix and went off for a ride. Changed out the main jet several times and pretty close now. Also adjusted the needle jet clip position. Engine ran very strong but some refinement still needed. I had an opportunity to try the lights and they worked great.

Rear brake functioned very well but front brake still needs some work. Front forks seemed a little stiff but were loosening up towards the end of the ride. Will have to see how that progresses.

I have to fit the bark busters and rear number plates.

I spoke with Will today and we are trying to have this bike ready for Sunday event.

Danny

[Zyx]

It will go faster if you put on some tank emblems.

[dcooke007]

GMC, I am not as young as I used to be and it takes me longer to heal now. Saving the ultimate performance improvement until I am a little more comfortable with the current performance level.

As I mentioned in my prior post the front brakes were not working very well. Little stopping power and brake lever felt mushy. In the first picture you can see the brake lever moves further with the axle removed. With the axle installed brake lever travel is reduced and the axle is under load. One brake shoe was contacting drum but the other one was not. At first I thought maybe the drum was out of round, unevenly worn brakes or ????? After examining everything carefully I flipped the brake shoes over on the brake backing plate and every thing worked normally. Brake lever had full travel and axle was not loaded with brake applied. I had replaced the brake backing plate and installed the brake shoes opposite their original orientation. If the brake shoes were new it would not have mattered. Shoes had to be installed as they were removed due to wear pattern for proper operation.

These are the Yamaha forks I mentioned previously.

This is what was on the left side of the front wheel. At some point an odometer / speedo may be added to this bike and the sl250 speedo drive allowed proper installation of the wheel assembly. Just capped off the speedo drive for now.

And this is a mdl 94 horn / dimmer switch I am using for an on off headlamp switch. Looks rough but works well. Brown wire going to voltage feed and light blue wire to headlamp. This bike is equipped with a single element 6 volt lamp.

Some more tuning to do tomorrow.
Danny

[Zyx]

I used that same horn/light switch for years as a kill switch. In about the same condition.

[dcooke007]

Finishing up the final details. Bark busters were not fit well and blocked access to the fork caps. Shortened, slotted, bent and installed with added spacer.

Finished jetting and engine now runs strong and clean. Some minor tuning still needs to be performed at track. Will is going to install the rear number plates with the proper bracket. So bike is ready to go and is now equipped with flux capacitor tank emblems for added punch. Now it is not a tired Combat Wombat.

Danny

[Phydeaux]

Nice work! Very enjoyable read and the pictures really made it all interesting.

Thanks!
RLW

[hodakamax]

Big fun, watched it all the way-- You're a handy sorta guy!

Max

[Zyx]

Extra 42 horsepower attributable to the tank emblems. Even digital cameras can no longer keep up with acceleration.

[wgahrmann]

Danny the bike looks great! Can't wait to pick it up, your attention to detail is amazing, I truly appreciate all of the time and hard work you have put into this project.

[dcooke007]

This is a link to a You Tube video from Will.
https://www.youtube.com/watch?v=NrGaR8V6L0E

Danny

[dcooke007]

Some pics for you. This was the Irish Valley Cross Country. You can see Will had a little trouble on the starting line in my previous post but he was starting to catch back up with the pack. I would like to tell you he caught them and placed well. Unfortunately had a piston seizure and the cylinder is back with me now. Bike will be here in a few days. We have a month to get ready for the next event. As Will said, that's racing.

Danny

[Dale]

Danny,
Thanks for posting the video and pictures. Great stuff. Sorry to hear that it seized up though. Looking forward to your analysis of what happened there.
Dale

[Zyx]

Was it a momentary seizure, or outright failure? Where on the piston and bore did it seize? Was it adequately broken in before racing? Common causes for high rpm seizure are leakage at the ring gap, and oil film failure under pressure. One would suggest paying close attention to ring gap during the rebuild, the other using more oil in the premix, closer to 20:1.