mcman56

The original Reflex carb can work fine. 1. The two ports on the side that connect to tubing are vents to the float bowl. As gas gets lifted into the carb, some air needs to go in. These need to vent to atmosphere. 2. An adjustable needle from a 70s street model 125 or a TL125 will fit. In fact, the Reflex carb is pretty much the same as a TL125 carb. They used to sell after market carb rebuild kits on ebay for XL or SL 125s. These came with the needle and that is where I got mine. Will the needle from your XR70 fit? Is it a similar length? You could try it. Shimming the original needle should also work. 3. A 100 or 105 main jet should be about right. These jets are the same as the 1990 XR100 and probably other years. 4. You can pull the cap off to adjust the idle mixture. 5. The pilot jet is different than most so is a bit more difficult. The original 38 was available from Honda but nothing else. It needs to be slightly larger to avoid the cough and die symptom. You can buy a tiny, #60 thru #80, drill bit set from a place like McMaster Carr and go one size larger than it is already. That is what I did. 6. You can remove the snorkle but I never did a comparison to see if it really helps. 7. You can even bore the carb out to the equivalent of a 24mm. It is a bit of work but can give a nice boost in top end power. If you look at the end of the carb that bolts to the engine, you see an oval shape that is non symmetric and oriented towards the bottom. This can be opened so the oval is symmetric top to bottom. The top of the oval does not become active until the throttle is opened so there is no affect on low speed operation.

I run the IRC tube type with no issues.

I started trials on a TY250 mono and it was a good choice. After a year or so, I changed to a '97 270 Gas Gas and my riding ability went backwards for a couple of months. Compared to the Gas Gas, the TY was very smooth and everything happened pretty slow so there was time for corrections. Looking back I should have stayed on it longer. Quick reacting bikes are great but need to be pointed in the right direction and can punish poor throttle/ clutch control

If yours is not a reflex, the forks are different. The Reflex has skinny (33mm?) forks so the valving may be different. 5wt felt fine until I got stiffer springs. Then, it seemed to deflect quite a bit on small rocky sections. Compared to a modern bike, everything happens slowly on the old Honda. I guess that includes the suspension.

Feetupfun That looks like a nice improvement. What did you use for a brake cable? It looks very Japanese. Thanks Dan

If it is a Reflex with stiffer springs, 10 wt @ 5.7" works. For me, 5wt was OK with soft springs but the front end felt "busy" over small rocks with stiffer springs.

If it is like a 2002 shock, it can be rebuilt. You just need to find someone to do it. Some info is at: http://www.trialscentral.com/forums/index....showtopic=28332 After the rebuild, mine feels like a new shock. I suspect fresh oil makes the difference.

Mr Woody, I'm getting further along in my build and realize that I'll need fork stops...at least with the original tank. It looks like I could bolt on some type of stop plate on the lower fork clamp Did you need to add stops to your bike? If so, how? Thanks, Dan

Does someone have a parts diagram or picture of the front brake cable connection to the brake for a 71 Alpina? A picture of what I have is below. I would expect some type of clamp or threaded piece to hold the cable but there is just a little bracket with a hole. Does the cable just float on top? Am I missing something? I'm not sure what to make of this. Thanks!!

I purchased a project C15 (1960) with no head steady and then bought one off of eBay. The one I purchased has a flat bar to connect head to frame clamp but it did not seem to fit so I used a simple spacer. It all fits together but is too wide and interferes with the gas tank. Is this the wrong head steady? Could someone describe what the correct one would look like? It looks pretty simple to make....maybe just longer where it attaches to the head. See the picture.

That is a good idea. I have a lathe. Do you have any pictures?

What would be a good length spacer for a C15? For the machined ones, are they aluminium?

I'm putting together a simple C15 for trials. The existing carb is a monoblock 376/ 258 and under the dirt/ cobwebs appears serviceable. I believe but am not sure that it has a 1 1/16" choke. Should this be adequate for trials? If it makes a difference, the engine has the standard cam and 40-441 head. (big valve - 11/16" choke per the RR book) The other option at hand is a 22mm TLR200 carb but the mounting is different.

I have had success treating elbow tendinitis and other forearm soreness with an "armaid". See the web site. It allows you to provide quite a bit of pressure when massaging tight or sore places. The first time I used it, I ended up with bruises on my arm. It seems quite expensive for a little plastic assembly but is effective. I have also found there are two different theories on tendinitis. A medical doctor will tell you it is an inflamed tendon and that you need ibuprofen. A more holistic practitioner will tell you that you have a tight muscle that constantly pulls on the tendon making it sore. If you can relax that muscle, the soreness will pass. http://www.armaid.com/

I did bronze bushes with grease fittings. Check out page 3 of: http://www.trialscentral.com/forums/index....26708&st=30 Some text is at the top and a picture further down. Honing to a very snug fit, I was also able to get less suspension play than with the needle bearings. That said, when I have has squeaks in that area it is the spherical bearing in the bottom of the shock. (CL12?)

What does it sound like and run like when it hits that limit?

I would clean the carb again paying particular attention to the pilot jet. Blow it out and look through to verify that it is clean and that all surrounding ports in the carb body are clean. Fresh gas would also be a good idea. If there is water is the gas, a little drop of water can attach to a jet and limit flow. It can be most annoying to diagnose and solve.

Aluminum work hardens as in... when it is bent it gets harder. Hard metals want to break rather than bend so you need to soften it prior to bending. You heat and then allow to cool prior to bending. I have used two methods to get the correct heating temperature. One was to coat the area with a black magic marker (it probably has a different name in the UK). The other was to coat with acetylene soot. (I suspect that the soap trick is similar.) Heat until the marker or soot is burned off. I straighted a Beta cast brake pedal that was bent into a full U shape. Since it was such a sever bend, I did it in three steps stopping to soften the metal in between steps.

I found some instructions and am attempting to disassemble for rebuild. The instructions I found say to clamp the head in a vise and then it implies that I can just unscrew the bottom. When I try this, the chrome shaft does not turn so it does not come apart. It looks like I need to grab the chrome shaft and turn it but that seems likely to damage the chrome. Are there any suggestions?

Question #2 What type of brake cable do these use? There is a tab with small hole on the backing plate that looks like the inner cable would go through. But... the lever that activates the shoes looks like it takes a barrel type end. The barrel would never fit through the little hole so I mudt be missing something.

Thanks for the reply. Are all Sherpa sliders/ mud guard mounts the same or do I need to be concerned about year of manufacture?

I have a set of 1971 Alpina forks on a C15. The forks came with no mud guard or mud guard brackets. I have seen a few pictures of Alipnas with high MX style mud guards but I want to run low ..trials, standard type plastic mud guards. What can I use for brackets? Where can I get them? Should I just make some U shaped Aluminium bends or would something stiff... more like a brace/ bracket be desirable? Thanks!!

Woody, What are you using for a brake pedal? It looks like I could use the original BSA or with a little work fit the Bultaco pedal. Thanks

Based on some recommendation, I built a fixture to hold the frame on a bike carrier mounted to a trailer hitch. Using a long lever in the swingarm pivot, I tried to bend it straight but the 7/8" SS spindle on my lever just bent. I heated the short tube between the swingarm/ engine mount bracket and lower casting and was able to straighten the piece. Upon assembly, the chain/ sprocket/ case alignment looks straight ...or maybe straight enough. That heavy duty chain does make everything very tight.

I just saw this reply. The chain is an RK 428 heavy duty... maybe the "heavy duty" makes it wider?? The gearbox sprocket is a newly purchased 428. The rear wheel is from a Bultaco Alpina which I understood also used a 428 chain. I'll measure the width. I did put the original C15 wheel on and saw the same thing. I looked closer at the frame and the rear motor mount/ swingarm mount is twisted a bit to the right and up. I have another posting with pictures on this. This sort of pulls the back of the engine to the right and into the chain. I have been pursuing straightening or replacing the frame.