TRX250R.ORG

Workshop => Suspension and Chassis => Topic started by: meathead on December 22, 2014, 02:33:32 PM

Title: Ride height
Post by: meathead on December 22, 2014, 02:33:32 PM

Howdy this is my first post on this site. and I am building a trx 250 R from the ground up. My first one. I've been a mechanic most of my life so I have the tools and enough knowledge to do the job. With a little help. I need to
know if I put a 88 dog bone ( shorter ) on a 86 Will that increase my ride height ?
 Thanks

Title: Ride height
Post by: Brian on December 22, 2014, 04:28:28 PM

Shorter dog bone will move the bottom of the shock up, so yes, it will sit higher.

Title: Ride height
Post by: meathead on December 22, 2014, 04:38:34 PM

Thanks a lot. I've got a set of ohlin long travel front shocks Will they work with stock a-arms?

Title: Ride height
Post by: Tbone07 on December 22, 2014, 05:11:13 PM

Quote from: meathead;47944

Thanks a lot. I've got a set of ohlins long travel front shocks Will they work with stock a-arms?

They will not

Title: Ride height
Post by: meathead on December 22, 2014, 05:15:30 PM

Howdy can you tell me why  they wont work ?

Title: Ride height
Post by: beobe99 on December 22, 2014, 05:55:22 PM

Long Travel shocks have a longer body (eye to eye measurement), they will bolt on if I'm correct, but will make the front end look silly high and may bind up causes damage when in use. Hopefully someone else can confirm or elaborate.

Title: Ride height
Post by: RyanWsly on December 22, 2014, 06:09:18 PM

The shocks need to be the mechanical stop not the a arms/ball joints, the long travel shocks are physically longer giving them more shaft travel so they will not be the mechanical stop on standard a arms. The mounting points are different on the a arms from standard to "long travel", they don't truly add travel to the front wheels they just give the person tuning the shock more shaft travel to work with.

Title: Ride height
Post by: meathead on December 22, 2014, 06:22:09 PM

Thanks guys for the bad news as it turns out. I guess i'll post them on e-bay and get rid of them

Title: Ride height
Post by: Pumashine on December 22, 2014, 07:42:42 PM

Can't he move the shock mounts to use the long travel shocks?

Title: Ride height
Post by: meathead on December 22, 2014, 08:06:21 PM

Even if I could that kind of modification is beyond what I can do

Title: Ride height
Post by: meathead on December 22, 2014, 08:12:09 PM

I kinda figured it would raise the front end but I didn't know that it would raise it so much as
to be impractical

Title: Ride height
Post by: meathead on December 22, 2014, 10:42:23 PM

Turns out that these ohlin shocks are not long travel with a length of 16.5 "  Man am I a
dumbass

Title: Ride height
Post by: andy@maultechatv on December 23, 2014, 05:19:12 AM

For every 1/4" of shock movement the rule of thumb is that it will change your ride height 1/2".  So a 2:1 leverage ratio.  You need to raise the frame 12" off the ground then measure eye to eye where the shocks bolt up and this is the correct shock extended length you need for the A-Arms you have.

Title: Ride height
Post by: meathead on December 23, 2014, 05:53:22 AM

Howdy Thanks a lot I can understand that. Stock length is 15.5 " So are you telling me my ride height is gonna be 2 inches higher than normal ? that I think I can live with. I wanted
to raise it about 2 inches anyway. that's why I put a shorter dog bone on there. a couple inches more ground clearance for trail riding isn't a bad thing. What is the normal extended
length on one of these.

Title: Ride height
Post by: andy@maultechatv on December 23, 2014, 09:17:17 AM

For the rear, if you run an adjustable dogbone, for every inch you move the ride height it will also change the compressed frame height.  So instead of bottoming 1.5" off the ground you will be bottoming your frame at 3.5" off the ground.  For stock A-Arms the normal extended length is 16.00"

Title: Ride height
Post by: meathead on December 23, 2014, 09:36:29 AM

Howdy Andy Well my shocks measure 16.5 inches. I don't suppose that extra 1/2 inch will make much difference What an inch of lift on the front?
I guess that is significant. But do you think an adjustable dog bone is the way to go? Because I heard that all they do is get longer to lower your rear end

Title: Ride height
Post by: andy@maultechatv on December 23, 2014, 06:38:34 PM

I would recommend against the adjustable dog bone as it also changes the progression on the rear shock. And .500" in front shovk length will raise the frame approximately 1.00" with the same springs, which is huge.

Title: Ride height
Post by: meathead on December 23, 2014, 08:01:17 PM

Howdy What about a shorter 88 dog bone Will that work without too many other problems.

Title: Ride height
Post by: andy@maultechatv on December 24, 2014, 10:34:33 AM

I would have to completely map it out on my linkage program to see what it would look like.  But I would have to get an entire bike in the shop first to measure everything up first

Title: Ride height
Post by: meathead on December 24, 2014, 10:53:16 AM

Well go ahead if you want to I'm sure there are a lot of people who want to know I know I've
been wondering about it for a long time Ever since I bought my frame. Like I said this is the
first one of these I'm building But thanks a lot for the info you've given me I really appreciate it.

Title: Ride height
Post by: The_Steve_Man on December 24, 2014, 11:14:14 AM

Andy,  I am courious about how these changes would be noticed by the casual trail rider?  Also have you done calculations for a 450r  swingarm on an R frame?  I know that is for another thread, but courious?

Title: Ride height
Post by: meathead on December 24, 2014, 11:34:36 AM

Howdy That's what I plan on doing a little trail riding High speed at times nothing  real
serious Just trying to get a little more ground clearance