Rough riding cmc

Tire size? Tire pressure?

My Spyder originally had VW normal 165-15s on it and I didn’t know any better than to run a typical 32-36 TP.

After replacing them with Beck-recommended 185/65-15 and 205/60-15’s and airing down to 20-24 psi, my ride softened up a lot.

Same with losing the Bilsteins it came with and going with the cheapo KYB’s.

Sounds like shocks that are too long and are bottoming out.  Very common problem on lowered VW’s.

KYB VW sedan shocks seem to give the softest ride, and the 20 front - 24lbs rear MAX should help a lot.  

How high is it from the ground to the top of the wheel well arch, front and rear?  Does it have an adjustable front axle?  When sitting on a level floor, is any part of the suspension sitting on the travel bumpers indicating that the suspension height is out of adjustment?

Other CMCs, including mine, have a reasonably soft ride, but the big ride differences come from (1.) smaller Tire size and (2.) too high tire pressure.  See Dave's post just above.

BTW, CMC never built ANY complete cars.  They were never set up to do that, only make bodies and aggregate parts for their kits.  They farmed some builds out to one of several auto body shops in the North Miami area so there isn't a lot of consistency of quality between them, but those were the cars that showed up in airports as marketing tools.

2'nd BTW:  LIRick brings up a great point:  I had that wrong size/too long shock thing on my car when I first lowered the heck out of it.  That's worth looking into as well.

@LI-Rick posted:

Sounds like shocks that are too long and are bottoming out.  Very common problem on lowered VW’s.

Listen to @Gordon Nichols and Rick above, both give good advice.

The front bumpers for bottoming the shocks are either integral to the shocks(modern style) or screw on the top(old style plastic dust boot/bumper combo). There are front shocks for lowered cars if you have stock spindles and are lowered down in the weeds.

Regular height shocks with drop spindles are pretty common today, but you'll need to look at what you have under there @Renfrance

Good luck.

#1 adjust (lower tire pressure)

#2 check shocks - most think the KYB Gas filled shocks are too stiff (at least on front).  Find inexpensive oil filled shocks --- or adju$table shocks.

I located my problem. I was using tire pressure on stated on the tire. It was 32 psi. I dropped it down to 18 in front and 22psi in the rear and what a difference. Again this sight has saved the day again. In the past week suggestions regarding my spinning shift lever and now the rough riding issue has been resolved thanks to all of you.
I cannot thank you enough.
Renfrance

I found my problem. My tires were inflated to the Tire specs at 32 psi and I dropped it at a suggestion from Wolfgang to 18 psi in front and 22psi in the rear. It made a tremendous difference. A big thanks to all who replied. This is a fantastic site.

Thanks for the suggestions. I found my tire pressure was way to high.

Thank you for the suggestion. I found the tire pressure was way to high. Lowered the pressure and it made a tremendous difference.

Thank you for the suggestions. It was the tire pressure. The tires were set at tire pressure suggestions on the tire. I lowered the tire pressure and it rises like a new car.

Sometimes it’s figuring out what question to ask that is the difficult thing ...  

@Renfrance posted:

Thank you for the suggestion. I found the tire pressure was way to high. Lowered the pressure and it made a tremendous difference.

You can say that again.

@WOLFGANG posted:

#2 check shocks - most think the KYB Gas filled shocks are too stiff (at least on front).  Find inexpensive oil filled shocks --- or adju$table shocks.

Yeah, when I was looking, someone on Spyderclub suggested the same. The more expensive Gas-a-Justs were too stiff but the cheapos work just fine.
I agree. Along with the lowered TP it’s just fine. Still stiff, it’s a light car, but it’s no longer back breaking.

Funny how shocks get credit or blame for such a myriad of problems when they really have such a simple job to do !..........Bruce

I have to say that my Bilsteins are a tad harsh on a rough road at times.  If they ever wear out, at this rate never, I might consider a more comfortable, say softer shock in my 911 front end and for the trailing arms in the rear.  

@aircooled posted:

Funny how shocks get credit or blame for such a myriad of problems when they really have such a simple job to do !..........Bruce

Agreed. I had stock COFAP shocks. They were OK but the front end dove too much under braking. I switched to KYB GR-2 and liked them better.

My new car has Koni adjustables, non-gas(they're NOS from the 80s or 90s).

I like the Konis the best, but the ride quality of all three was way more dependent on tire pressure than which shocks were installed.

I was going to mention this the last time tire pressure was brought up but forgot:

Something I first noticed on my Smart car, probably because it’s short, relatively light (like our cars) and rides on low profile tires: On the OEM shocks the ride was horrible. You had to seriously pay attention to road condition because if you hit anything more than a 2”-3” “irregularity” it would jar your teeth loose.

I switched to gas-filled Bilsteins after about a year of ownership which helped a lot, but I noticed something interesting. The ride was much harsher when the TP was low.

I surmised it was due to the sidewalls of the under-inflated tires doing the work (poorly) of the shock absorbers.