75 250 MX Shock Position

[Tahitian_Red]

I've read the 74-75 250 MX tips in SKT and it says they ran their shocks in the 4th lower postion and upright upper mount.  I have some questions about this.  

Is it better from a steering and handling standpoint to run 14.25" shocks in the normal position (with spacers to limit travel) or 13.5" shocks in the laydown position with spacers also?  I have only seen one picture of someone racing Vintage with the shocks in the laydown position.

Now assuming each will steer the same does it hurt handling to have the 13.5" shock shaft only move an inch and half or so vs. the 14.25" shock shaft move 2.5" (estimated)?



The "Factory Novice"

[Larry Perkins]

When the shock travels less the damping is limited so it is not good to run laydown in Vintage but cool for PVMX.  Plus it is a lot harder on the shock.  The hot ticket is to run at the top mount by seat and on the bottom go to the very back one which was originally intended for laydown.  As always you have to spring to match this position.  I can not off the top of my head remember the shock length for this but Teddy Landers could tell you from memory as he has several set up this way with Ohlins.  If you can not reach him let me know and I will look it up.

Larry P

[Tahitian_Red]

Larry,

Setup like this bike?  Is that a 78 pipe on there?



The "Factory Novice"

[brian kirby]

Jay, that is Teddy, that is the shock setup Larry was talking about.

Brian

'73 Berkshire

[Larry Perkins]

Brian is 100% correct.  I think that is a 420 pipe on Teddy's 400 if I am remembering right.  He could tell you for sure.

Larry P

[Tahitian_Red]

I did a search and I think Teddy might be running 15" Ohlins on the "Mint" 400.  

Darn, I've got 13", 13.5" and 14.25" Ohlins, but no 15".  Time to sell some parts.

The "Factory Novice"

[gooddirt]

Just go to the next hole with the 14.25 shock.  Jay look at my posting under 'A few fun photos' you can check out my 1974.5 250 ktm  photos. In the one photo with me next to the bike shocks are NOT in the correct hole. [8D] LG

[brian kirby]

I agree, dont go out of your way just to get 15" shocks if you already have 14.25's its not that big a deal. Just move the lower mount to the rear most hole of the front set (IE one forward of where Teddy is running) and run with it.

Brian

'73 Berkshire

[tomale]

Red, back in the day Protopipe made an up pipe that fit the early MC5's and if I remember there was some talk of Ace  making some pipes like it a couple of years ago. The cool thing was that it had a tapered header pipe and used several other die pressed pieces. It looks like the 78 pipe but actually came out in Oct. of 76. I know they used my brand new 76 MC 5 to build it... If you could find one of those to would be a real coup. As far as I know, only my friend Tom in Denver has one and me...and mine iw not going anywhere... It could be mistaken for a modified 78 pipe but they are not the same. I would think that it would not be too difficult to modify that pipe to fit a highbreather frame...One of the benifits is that does not stick out as far in the back of the bike as the 78 pipe does. that would meam that the R side panel could be modified too to not stick out so far....

Thom Green,Still crazy after all these years!
76' 250 MC5 (orginal owner)74'
250 hare scrambler (project bike)
72'sixday (project bike)

[Steve Minor]

Don't forget that changing shock length, ride height, etc sometimes causes the chain to drag on the swingarm....a Teflon block and some heavy duty tie wraps or safety wire is often an easy fix....

Steve Minor
Wilmington, NC

[Tahitian_Red]

Steve thanks for the reminder about the chain.

I should be alright because I'm just trying to find a shock length and placement that reproduces the same geometry as the stock laydown position.  I'm just trying to get the shock working to it's maximum with the travel limiting spacers.


The "Factory Novice"