Covenant Conversion

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Hi all
Just took my front Road Holder shock assembly apart to install some new main tubes, bushings and seals and it looks like I got some parts missing from the P.O. attempts at fitting things back up right. The Damper tube cap (061347)… is toast on both sides. One looks like it was pounded into oblivion. Also the damper rod seat (030585) wasn’t even there at all so… all is not well in Paradise. What I would like to know is, whether the Covenant Conversion is available for the Commando, or should I just get original replacement parts and just go for the triple rate spring conversion. I am in Canada so I am wondering if parts could be had locally??? Any input would be appreciated. TY.
 
The Covenant fork kit is available from RGM motors and is about ten pounds sterling. You may be surprised to find that it consists of two small alloy dowels to block up the existing holes in the damper rod (you then have to drill two holes higher up the rod) and two thin alloy tubular collars that slide over the fork tubes between the lower bush and the top bush and prevent the tube from topping out on the damper rod and damper tube at full extension. That's it! So you will have to purchase all the other parts that are damaged as none of these come with the kit. Once you see what the Covenant parts consist of you will probably make your own in future, I got a machine shop to turn me up enough collars for four sets of forks for the same price as one kit and I will simply braze the holes closed in the damper tubes. RGM also have alloy damper tubes available with the holes pre-drilled higher up but I am sure they come without the screw cap. On the bright side I have found that this simple conversion makes the forks much smoother in operation and is a cheap and worthwhile modification.
 
I certainly agree with dave M. I fitted the Covenant conversion (from RGM) to my Commando along with progressive springs and it is a definite improvement.
 
Commando front forks left stock have lots of room for improvement. The front end has only 4 ½ inches travel in stock commando form. If you check each end of the travel you will find a mechanical clang at each end. My bikes toped out real bad, and my friends bottomed real bad. To make matters worst you use up an inch or one and one half of the 4 1/2 when you sit on the bike.
We started to fix this by buying and installing the aluminum fork dampener tubes from British spares in NZ and installing “the Coventry kit”. They come with the oil flow holes in a new higher position so as to address the top out problem with a fluid stop. But “the kit” also added loose fitting bushings 1 ½ long between the steel bush and the top high hat bush.
What is more important is the over all travel. The threaded rod that supports the valve in the dampener tube down in the oil is the mechanical limit of the downward movement of the sliders. The clang you hear on top outs is the dampener valve hitting the alum. Cap on the dampener tube and it is held by a two mm dowel. This rod screws into the fork cap and is held in place with a lock nut.
It’s not a bad idea to increase the length of this rod by two inches so you get 6 inches of travel. We have done this with the use a kit with new aluminum rods that are two inches longer than stock. And adding Ford valve springs 2- 9/ 16 long one spring on each set up. We replace the old stock thick washer with four grade eight thin washers, two for in-between the new progressive springs and two under the reused jam nuts in-between the extra springs and jam nuts. If you have already installed the Coventry kit, you will need to remove the extra aluminum bushings that you installed with the kit. They limit travel and are no longer needed for top out dampening because you have put the valve that goes up and down in the tube on the end of the rod deeper into the oil. Now your getting 1 ½ more travel and the rod is two inches longer to keep the valve away from the cap on top outs. It may be found that if you have the more modern dampener tubes with the holes in the tapers they may work as is. Your steel dampener tubes can be changed buy blocking the holes at the taper on the bottom of the tube and re-drilling them so that the new hole is just on top of the taper. So now the bottom of the new hole is even with the top of the taper.
The new aluminum dampener tubes already come this way. I moved them when using the old steel tubes on another bike because the new tubes have the holes moved up off the taper. You can add holes smaller and higher yet to tune the fluid stop but this must be done for the rider’s weight. The aluminum dampener tubes have to use 8mm fine tread bolts to hold them in the bottom of the sliders and are not provided with the new tubes. So you need to buy them. We use a longer bolt that stock because the thread is in aluminum.
The thing we are after here is a more compliant working front ends with fluid stops at each end. Depending on rider weight I like to see at least 1 ½ inches of settling when the bike is sat on by the rider. We have been using ATF for fluid and the ride is very good. I have two Commando’s one with stock springs and one with Progressive’s I like them both but they are quite different. The stock springs preload the set up much higher this makes using the center stand a little unstable as it’s not quite tall enough for flat ground now. But having two inches for potholes and four inches for bumps is real good. We now make kits for this mod and they are 55.00 us dollars plus shipping. You get two new alum dampener rods. Two new ford valve springs, two new 2mm dowels and four new grade eight washers in the kit. Fine tuning the kit to your needs is your project. Pre- loads, springs, fluid types can all be played with for best results. Norbsa
 
Norbsa, have you experienced any fork flex with this new modification? I did something similar on a japanese dirt bike during the days when long travel suspension was just coming in and while the suspension was more compliant and had a longer stroke the steering acuracy suffered a bit. I found that when the fork bushes had some distance between them at full stretch (ie standard) they were more resistant to twisting. I like your idea of getting more travel from the Norton forks and may try this on my next project (a Norton flat tracker for the road) but would be inclined to supplement this with the Norman Hyde fork brace which incorporates a pair of additional bushes for support, especially if using a single disc brake set-up. Does your modification make the bike taller at the front at rest and if so have you tried a slightly longer shock absorber to re-set the geometry, or is this not necessary? It's very handy to have our very own R&D department, keep up the good work.
 
Yes the brace is good if you drive real hard. I like RGM's better than Hyde's It's plainer and is not as hard to install. But both kits are hard to install and are not needed by the adverage Commando rider. If your going with large disk brakes or duals get the brace. Please understand that when the front end is at it's weakest it's at full extension and it is not fully extended during hard corners and or braking. So yes at a stop light or gasing it on hard the front end comes up all the wayand is weak but it's not weak when you need it to be strong. norbsa
 
Thanks for the Great forum

Thanks for the quick response to my question. I’ve got the progressive springs and bits that were missing or broken on order and I’ll make a call to get a covenant conversion kit. Great Forum! 8)
 
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