Race Tech Gold Valves in Betor forks

Schwany

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I am in the process of installing Race Tech Gold Valves in my old Betor forks on the P11 to see if I can soften up the harsh hit on square edged bumps. It is a road only P11, and I need a plusher front end. The harsh hit is mostly due to the forks being old and me not changing fork oil and cleaning them often enough. Race Tech claims their valve makes old forks potentially better. They call it a cartridge emulator. Could all be BS, but I'm going to give it a go anyway. If you want to know how it all works check out the Race Tech dot com website.

I forgot to take a before picture of the damping rod. Below is an after damping rod modification picture. The stock damping rods have a pair of small holes just above the foot. The silver alloy lump at the right end of the rod in the pic is the foot. What has to be done is open that existing set of holes up to 1/4" and add 4 more 1/4" holes for a total of 6 in each damping rod. The valves go on the top of the damping rods, and shorter springs are used. I have to cut spacers to make up the proper spring pre-load. I've also spent a couple of hours with a hand file smoothing out and cleaning up radiuses on parts that didn't slide that well. Anyhow, all pretty simple stuff.

The valves and springs are supposed to arrive tomorrow. I'll take a pic of them in the assembly orientation on the damping rods. I might get a ride in Sunday with the valves installed. That's the plan anyway.

Race Tech Gold Valves in Betor forks
 
This is how the Gold Valve setup lines up in an old Betor fork. The spring goes on top of the Gold Valve, and the pre-load spacer above the spring.

Race Tech Gold Valves in Betor forks


I ran into one issue installing this bunch of parts and that was the piston/adaptor ring (shown below) was overly tight in my old 35mm stanchion tubes. It was a bear to install and did not move freely in the stanchion tube, but I put it all together anyway. Not good. I thought it was the correct size and would start working correctly when I filled the forks with fork oil. Not even close. I wouldn't take it out of the garage it was so damned stiff. So I pulled the springs, pulled out the Gold Valve with a monkey hand grabber, and made a tool for the piston adaptor and fished the darned thing out. I then file fit the piston ring. Fortunately, is is some kind of plastic, nylon or whatever that was easy to file.

Race Tech Gold Valves in Betor forks

Race Tech Gold Valves in Betor forks


Once I got the rings filed so that the piston adaptors went in without a lot of difficulty and slid inside the stanchion tubes like they should, I stacked everything up in the stanchion tubes, put the caps back on, and took the P11 for a spin.

The Gold Valve did soften the harsh hit on sharp edged bumps and make for an all around smoother ride. Compression damping was great and dive control on the money.

I realize the information herein is for a limited audience and not for Norton Road Holder forks, or whatever came on P11's. Many people put Betor and Ceriani forks on Nortons in the days of old. I was one of them. The Race Tech Gold Valve does help improve Betor forks built in the 70's. Is it worth it? Depends on your wallet I guess. The kit is not cheap at $427 delivered in the USA, and it won't turn a set of old Betor forks into $3500 Ohlins USD forks. For me it was cheaper than sourcing a set of somewhat modern used forks off ebay of unknown quality, and rebuilding them and fitting brakes, axles, and so on. I do think the kit is a bit over priced, but not terribly so for someone that could use an improved front end, and likes to ride at a good pace whenever possible. If one is comfortable ripping into their forks, installing this Race Tech Gold Valve kit is not much more difficult than replacing seals, which should also be done at the same time BTW.
 
Thanks for writing all of this up Schwany.

I, on the other hand, intend to remove the Betor forks on my rough & ready P11 and go back to as originally fitted Matchless teledraulics. My Betor set up never accommodated the front brake torque stay correctly and created a twisting motion that made the front brake scary to operate. If you're interested, I'll give you 1st dibs on my takeoff Betor stuff. But don't hold your breath as I won't get to it for quite some time. Jer
 

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Thanks for writing all of this up Schwany.

I, on the other hand, intend to remove the Betor forks on my rough & ready P11 and go back to as originally fitted Matchless teledraulics. My Betor set up never accommodated the front brake torque stay correctly and created a twisting motion that made the front brake scary to operate. If you're interested, I'll give you 1st dibs on my takeoff Betor stuff. But don't hold your breath as I won't get to it for quite some time. Jer
Yeah, the Betor forks need a fork brace loop over or under the front fender on my bike, and it would have to be a custom one off. I think about making one, but never get around to trying to design one. My Betor forks are the Sport VHC version and have a slightly different design from what is shown on the Blue P11 in your pic. If those are Betor forks that is. My front brake isn't that scary, but the fork does twist the fender a little when I grab some brake. I only see the fender move a little in the garage though. On the road I'm looking way ahead. With the light crank I have my motor slows down quick when I get off the gas when pretending to go fast out in the twisties. I don't have to use a lot of brake unless something crazy happens in front of me.
 
For future ref, the rings are made of PTFE. You can reduce the diameter by first cutting material from the ends of the ring as per grinding the ends of the piston ring to increase the gap, then if the ring bottoms out in its mounting groove filing the ID until the ring slides easily in the bore.
 
For future ref, the rings are made of PTFE. You can reduce the diameter by first cutting material from the ends of the ring as per grinding the ends of the piston ring to increase the gap, then if the ring bottoms out in its mounting groove filing the ID until the ring slides easily in the bore.
OK, PTFE it is then. I'll try to remember that in the future. No guarantee though. :)

File to fit rings is how I put the process. Knowing how to do it I thought was understood. Thanks for the clarification for those that don't know what I'm talking about.

In the case of the piston/adaptor rings on my set up, they were not close to bottoming out against the piston in the piston ring groove. The ring diameter was too large for an easy fit with the ring ends butted up against each other. It would have been real helpful if the Race Tech instructions mentioned the rings may need to be filed to fit if the pistons are at all difficult to install. It would have saved me some time. I made the mistake of thinking everything was ready to go. Should have known better.
 
I got an email back from Race Tech after I suggested they add a note regarding the possibility of having to file to fit the piston/adapter rings for Betor forks. Matt the vintage motorcycle technical rep said they do run into this issue occasionally with Betor and Ceriani forks. Manufacturing variations back in the 70's. He said it is OK if the rings are over filed to the point of having a small opening at the ends, or if the rings are removed entirely to get a fit, but having the rings is better than not having them. Also said that having the piston/adaptor without the rings is better than the stock fork. Only thing that is bad is not fitting the rings and leaving them on when the piston doesn't slide in, which will cause piston stiction. All that is logical, and I figured as much. Although I did not know removing the rings entirely would still work in a pinch.

As I mentioned, I filed the rings so the piston/adaptors slid in, but the ring ends were butted together. Will see how it goes.

I don't know if they will be adding a note about piston adaptor fit, but I still think it would be a good idea.
 
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