Progressive Monotubes

Last fall my brother Monty started asking me about the Traxxion suspension I have on my Goldwing. We talked about what was involved and even got some installation pricing from Paul at Midwest Custom Cycle Work in Evansville. $3400 with the billet triple trees, $2700 without. Those prices are with Paul doing all the work and include a night's stay in a hotel if needed.

About this same time Progressive Suspension started advertising a monotube replacement for the GL1800s. The cost for a set was only $275. They also make them for Harley touring bikes and owners have good things to say about them. I told Monty this might be a cheaper alternative. Unfortunately, like a lot of new products, the release date kept slipping and slipping. It wasn't until the summer of 2012 that GL1800 owners were able to get the monotubes installed and the evaluations started to show up. They were overwhelmingly positive.

I sent my brother a list of things for a suspension upgrade. He asked my opinion of going this route compared to a Traxxion system. I told him it was probably 80% of the improvement for 1/4 the cost. I also told him if the monotubes didn't cut it he was only out the cost of the monotubes. Everything else could be used with a Traxxion upgrade. He ordered the stuff from Wingstuff.

This writeup will hit the highlights of the work I did. It will not be a step-by-step writeup. The detailed steps can be found on Fred Harmon's videos (recommended), You Tube, or other places on the internet. The monotubes come with excellent instructions.


My brother came over and dropped off his bike and the supplies.


Fork rebuild kit. $99.


All Balls steering stem bearings. $40.


Kuryakyn fork brace. $170.


Progressive rear shock spring. $83.


Progressive monotubes. $280.


When I started tearing his bike down I found his left fork had been leaking.


These parts on the left fork rod have to be transferred over to the left Progressive monotube...spring seat, oil-lock spring, oil-lock valve, and retainer rings. They come off easily. These parts have to be removed before the fork rod can be removed from the fork tube. Getting to these parts requires separating the upper and lower fork tubes. I did the left fork first since it is the most complicated.


Here are the above parts along with the two 'piston bands' that need to be reused. They come off easily as well.


The left fork ready to be assembled.


Here are the two piston bands transferred to the monotube. I've also slipped on the new top-out spring.


The black spacer on the left is a spacer that is inserted. The black piece on the right is part of the monotube assembly. One spacer is inserted for a rider of normal weight like my brother. A heavier person would get two spacers.

Update 2013 - As more and more people have used these the consensus is if you weigh less than 200 lbs don't use a spacer at all.


Here are the other parts in the order they go on.


The parts reassembled on the left monotube.


I used a piece of schedule 40 PVC pipe to drive in the bushings and seals.


Here are the rebuilt forks. The 2006 and later bikes have an extra seal and ring in the left fork. These aren't shown in Fred's video so I had to do some internet research.


Kuryakyn fork brace. I like the way it is contoured to fit over the dust seals.


The original air filter with ~37,000 miles on it.


Stock vs Progressive rear spring.


The finished bike. Cost $672. It took about three 8-hour days to do everything I did. Replace the suspension. Replace the fork seals and bushings. Replace the steering stem bearings. Flush the brakes, clutch, and radiator. Replace the final drive oil. Replace the air filter. Install a CB. Refill the shock actuator. Run a ground wire from the battery to the ground point under the gas tank.

I took the bike out for a test drive. The forks are stiffer and the bike sets higher. It has a nice ride. It handles well in the curves. It is a definite improvement over stock and money well spent.

Traxxion vs Progressive? I told my brother 80% of the improvement for 1/4 of the cost. After riding I'd say AT LEAST 80% of the improvement. Both systems soak up bumps about the same but the Traxxion system gives a little firmer ride and should handle a little better. I think the Progressive system will be the best value for the majority of riders. Time will tell how the Progressive monotubes perform as they age.


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