Choosing the correct shock

Call Progressive with the details and they will help you.

We've found Dave Gardner with Ikon Suspension USA out in San Francisco to be very helpful, especially if he has the original shock. His email is: ikonusa@gmail.com

I spoke with YSS today about their shock. I could return it and have them put on a stiffer spring (present one is 167-280 Lbs/inch, new one would be 250-335 Lbs/inch).
However the damping action of the shock is very soft in spite of being on the firmest setting and there's a po-go effect when I push on the fender and let go. I asked for a quote on a stiffer shock and spring.
Trying to get an idea of how strong a certain shock and spring should be has been difficult. It's been like a guessing game. "We can make it stiffer"
I can tell a technician how much the sidecar weighs but most of the people I've spoken with make shocks for bikes and try somehow to apply that knowledge to a sidecar.
What should be the desired ride characteristic-firm, very firm or rock hard and how do you make sure you get that when you place an order?
Howard

My Hannigan Classic Twin has a Progressive shock and spring. One click past the lightest setting seems perfect for 150# passenger. When car is loaded for a trip with 250-300# of tools and camping gear I increase one more notch with the spanner. Everyone is different but this works for us.

Do you know the model and number of spring/shock?
I'd like to know the spring rate.
Howard

Shock choice is a hard question as there are ay least a zillion variables invloved. I could tell you that we typically use a 120/170 spring rate shock but it would mean nothing unless you were to mount it at the same place on the swingarm as compared to the spindle/pivot point distance apart , as we do and at the same angle etc.. The width of the outfit comes into play as does wheel lead an dother things if one would want to get into a splitting hairs discussion. Even at that there would be no speacial one size fits all answer. Seat of the pants means a lot out there and always will.
I can say that in most cases a sidecar shock that is stiffer rather than softer will provide the best overall results ans give better handling inder all varied conditions.

Claude,
I'm inclined to agree that there's a zillion variables and there's no one size fits all shock.
Besides stiffer rather than softer, what are the ride characteristics I can expect a correct shock/spring to produce?
Howard

gilberth - 7/1/2012 7:47 PM

Claude,
I'm inclined to agree that there's a zillion variables and there's no one size fits all shock.
Besides stiffer rather than softer, what are the ride characteristics I can expect a correct shock/spring to produce?
Howard

Ride characteristics will vary with the outfit. I really hate sounding vague but different sidecars will ride differently. A GL100/ Hanngan GTL or SP2 outfit will not ride like a dfual sport based outfit nor a HPS combo..a corvetter and a Lincoln are different too.
Are you building your own chassis? Sorry if you said that and I missed it.

Claude,
I've got a Jawa/Velorex 560 on a '74 Moto Guzzi Eldorado.
What about some kind of universal static assessment? For example, when I push down on the s/c fender, the s/c goes down then up, then a slight down and then a final up.
Would I be correct to say that a sidecar when pushed down should not pogo but come back up once and stay there?
The shock is on the stiffest setting and the spring rate is 167-280lbs/inch.
Howard

Gilberth,
that sounds more like oil is gone or the damping rating is low. (like the original shock from CB650 from Honda)
Many years ago I used Koni shocks on my CB650. Spring rate changes did not make as much improvement as the change of the dampening rate with just a turn of the thump.
I loved that feature and would buy it again in case I need to change shocks.
Sven