86 250r suspension

[Autophysn]

Just picked up a trike that has been sitting for 10yrs un-desturbed. The shocks seem very weak, I am a heavy guy. Can I just add more air (or ? ) to the shocks to make it suit me? My weight, 325lbs.

[edog]

Just picked up a trike that has been sitting for 10yrs un-desturbed. The shocks seem very weak, I am a heavy guy. Can I just add more air (or ? ) to the shocks to make it suit me? My weight, 325lbs.

You can add 1" PVC spacers on top of the front springs to stiffen it. Don't add air to the front forks. You may need to have the shock re valved and a new spring added.

[Yamatrike400]

Can i ask why you shouldn't add air?

[atctim]

because the front forks were not designed to operate with air - they were designed to operate with fork oil. This is like asking - "can I ask why I shouldn't put whiskey in my gas tank".

[edog]

because the front forks were not designed to operate with air - they were designed to operate with fork oil. This is like asking - "can I ask why I shouldn't put whiskey in my gas tank".

Whiskey mite mite be cheaper than gas.

[Dammit!]

They were advertised as having "air adjustable" forks but it's a terrible way to set them up. You should use the air valves to bleed air out only (air pressure will build up with different atmospheric conditions). Putting any real air pressure in there will just make the seals leak faster. Not to mention the action of the forks feels like crap with air in them.

As was mentioned, spacers are the best way to stiffen them up. Get some thick type 1" pvc and cut equal sized pieces off (up to 2 inches). Make sure to sand the edges so no loose particles are there. Install them on top of the spring (make sure the front wheel is lifted off the ground before taking the caps off!) and change your fork oil while you're at it. You can use ATF but I have always preffered fork oil.

The rear shock can be stiffened up using the preload adjuster at the top of the spring.

Edit: since you just got that thing, in addition to cleaning out the carb make sure you get rid of any old gas in it and check the air filter. It might look fine but grab it and see if it falls apart. The old foam ones degrade over time.

[edog]

The rear shock can be stiffened up using the preload adjuster at the top of the spring.

Hes going to need more than preload at 325 lbs.

[Dammit!]

Hes going to need more than preload at 325 lbs.

Max preload will get him by until he wants to send the shock out or upgrade it.

[edog]

Max preload will get him by until he wants to send the shock out or upgrade it.

Agreed......

[Autophysn]

okay, I have no idea of how the forks are designed. I will do some research into this one. I really appreciate the info, hell, I may have just pumped air in them. That would have sucked. But yes, I will need to do something about the suspension of the bike over all. For my weight, I will bottom this thing out very easily. This is going to be interesting.
By the way, the brass knob going to a tank just behind the carb. What is that thing, or better yet, what does it do? Is that how you adjust the rear shock?

[Red Rider]

okay, I have no idea of how the forks are designed. I will do some research into this one. I really appreciate the info, hell, I may have just pumped air in them. That would have sucked. But yes, I will need to do something about the suspension of the bike over all. For my weight, I will bottom this thing out very easily. This is going to be interesting.
By the way, the brass knob going to a tank just behind the carb. What is that thing, or better yet, what does it do? Is that how you adjust the rear shock?

Yes, the forks were designed to be air-adjustable, and anyone who says the airvalve on top of the forks is "for letting out the built-up air pressure only" doesn't know what they're talking about (a lot of misinformation spreads like wild fire on these boards). Now, that being said, the fork action gets very stiff very quickly when air is added. Most people use an air compressor to add air to the forks which will quickly pump them up to 10+ psi. If you want to use air to stiffen up the ride, your fork seals & bushing need to be in tip-top shape, otherwise the fork seals will leak for sure. Also, don't put in more than 1-2 psi per fork leg, & make sure you get equal pressure in both fork legs. It's probably easier to just add the pvc spacers, as has already been suggested.

The brass knob (it's actually gold anodized aluminum) that you were asking about is for adjusting the rear shock's compression damping (17 positions). There's also an adjustment screw at the base of the rear shock, on the righthand side, that controls the rebound damping (12 positions). Good luck.

[Autophysn]

NICE! thank you

[3Razors]

325 pounds is alot of weight for that bike, more weight than the actual bike itself. I don't know what the recommended weight capacity is on a 250R but I'm guessing its in the low 200's. I don't think any air or spacers is going to help that much, if you ride aggresively def. going to have to invest in a heavier shock/spring combo.

[Autophysn]

I can be agressive, but not stupid. I can't afford to get hurt. Stay slow on jumps, and mainly cruise around with the kids. But every now and then