This is one of those re-occurring questions. I think we should have a
spridget
FAQ.
I volunteer to collate and maintain it.
I can cope with many of the issues *but* I know NOTHING about the rubber
bumper midgets. It is the only model I don't own! So I'll need help there.
If you have any suggestions for questions that should be answered in the
FAQ, just send me the question(s) in an email message with the subject
"FAQ Question"
I will ask you or the whole list to provide an answer to that question if
it is beyond my level of expertise.
Now to the shock oil question.
A couple of years ago, I did a lot of chasing around to find the answer
to this question. Here is the summary:
- don't use engine oil, it will foam and multi-weight is not what you really
want anyhow (you want a stable viscosity over a range of operating
temperatures)
- Lever arm damper oil is available from Penrite. For all intensive
purposes it is identical to 20wt motorcycle fork oil and Auto Transmission
Fluid. All three have the same additives (anti foam especially).
- While you can vary the weight of the oil (i.e. 30 or 40 wt fork oil), you
may do internal damage to the lever arm. The correct way to increase
the damping is to revalve the shock. Peter at World Wide Imports (who
has mighty fine rebuilt shocks BTW) explained this a while ago.
- If your shocks are worn, they certainly won't put up with the heavier
weight oil.
Having said this I have used both 30 and 40 wt oils in my race car's
lever arm shocks, but this is only for smooth race track surfaces. What
I am controlling with the heavier oil is *not* bump damping, but rather
transient roll (i.e. the sharp roll induced by turn in). On a bumpy road
the oil would be way to heavy.
For my road/rally car I am using Peter's re-valved and rebuilt lever arms.
I had previously used 30 wt oil in this car. I am much happier with the
20wt oil and the revalve!
Mike
-----Original Message-----
From: Paul A Asgeirsson <pasgeirsson@juno.com>
To: endicott@nashville.com <endicott@nashville.com>
Cc: Andrew.Griffith@ReadRite.com <Andrew.Griffith@ReadRite.com>;
spridgets@autox.team.net <spridgets@autox.team.net>
Date: Thursday, October 22, 1998 9:35 AM
Subject: Re: Shocks.
>
>
>
>On Wed, 21 Oct 1998 17:21:53 -0500 Mark Endicott <endicott@nashville.com>
>writes:
>>Andrew Griffith wrote:
>>>
>>> Has anyone ever attempted to improve their road handling ability by
>>going to
>>> a thicker oil in the front shocks?
>>> My front-end was very bouncy... it was like the shocks weren't even
>>there
>>> much less working. So, I pulled the shocks off and discovered that I
>>was a
>>> little short on oil, only about half full of very gray oil. I looked
>>over
>>> the used oil closely and since I didn't see any sizeable aluminum
>>particles
>>> I figured I'd just clean them up and see how they'd work before I
>>replaced
>>> them, as you all know they are not cheap to come by.
>>> I pumped a lot of brake cleaner through them and when dry I gave
>>them a good
>>> shaking to try to gauge the piston slop, didn't hear much. I was
>>able to
>>> find some buna-s o-ring seals that fit and now I'm ready for oil...
>>any
>>> suggestions?
>>> A friend on mine said he used SAE 20W-50 engine oil in his Midget,
>>but it
>>> was creamed by a drunk before it ever saw the road.
>>> Could the internal friction of the shock actually heat the oil to
>>the point
>>> where it would start to thicken?
>>>
>>> -Drew
>>> '62MKII
>>
>>Drew:
>>
>>At the risk of being a nonconformist I put Red Line Synthetic 30 WT
>>Motorcycle fork oil in my shocks last year. It fixed my bounce and
>>has not leaked a drop in about 4k miles. I think if I were to do it
>>again I might use the 20 wt version of the same stuff. I think it's
>>just a little stiff for my taste as road car...
>>
>>--
>>Mark
>>70 MG Midget
>>Nashville, TN
>>
>>
>Motorcycle shock oil has been my choice of shock fluid for ages. Some
>come with "seal swell" that will often give a little extra life to your
>shocks.
>
>When I lived in Colorado Springs awhile back, I discovered with my Morris
>the simplest way to uprate the shocks was to drive around in zero degree
>temperatures.
>
>WOW! What a diference!
>
>Paul
>PAsgeirsson@juno.com
>
>or call Juno at (800) 654-JUNO [654-5866]
>
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