Trials Australia Forums

David Lahey wrote:

JC1 wrote:Yes, I'd have thought circa '75 too Dave
Notice in the pic with the Homerlite unit that it has been cut to make it fit around the top shock mount.

Nice frame. From what I've read, that's the one to have.
The early SM frame was said to have the footpegs in the wrong place.

I noticed the pegs were further back than the model 80 and model 49. I'm sure there will be lots more revelations along the way.
Have you seen this story?
http://motoeuro.org/sm552.htm?fbclid=Iw ... z7WIXyS6p4
I noticed that my frame looks like the one in this story but the bike in the story has later type triple clamps than what was on mine in the UK

Yes, I just read that article recently Dave.

One post on TC said he'd heard the first # in the VIN was what series SM frame it was eg VIN 235 would be 35th frame in the 2nd series, but I think it more likely that it was the year of manufacture, ie 1972. Some of the VINs mentioned on TC are in the 700s and I think it likely they were from '77 (the later style frame) as I've seen no evidence anywhere that there were 7 series of SM frames.

Footpeg location is interesting. It's difficult of course to determine if bikes on google images have original peg location or modified but given the plated frames probably most pics are of original peg location.

The first frames appear to have used the bolt-on early sherpa pegs,
then they were welded on the swingarm pivot plate just under the pivot, ie fairly high.

Then they were welded on the rear frame-tube and a fair bit lower,
then like yours on a plate behind the rear frame-tube.

Interesting information on the frames. I have an SM frame, number SM49. It has a M49 engine and a slimline tank. The bike is in the USA still.

This is a pic of frame SM49

Heck, SM frames are everywhere all of a sudden!
(Well, a bit of hyperbole never hurt anybody)

Nice to see.
Even nicer when we see them in action in due course, hopefully.

Well the frame number certainly fits with the JC interpretation

With JC's help it is clear that this SM frame is a 1975 design and that a model 80 slimline type fibreglass tank will fit once the rear edges of the side panels are trimmed back.
I'm in the process of deciding what to do about a motor for it.
The Sherpa T motors I have available to use are model 49, model 80 and model 198. There is also a model 158 cylinder which could probably be fitted to one of the model 49/80 motors to make it look right.
The motor that came out of the frame (model 159 I think) is available but would cost a lot to bring out from the UK (freight cost alone is $620).

This is to show how much of the side panels need to be trimmed back

Hi Everyone,

David Lahey wrote:With JC's help it is clear that this SM frame is a 1975 design and that a model 80 slimline type fibreglass tank will fit once the rear edges of the side panels are trimmed back.
I'm in the process of deciding what to do about a motor for it.
The Sherpa T motors I have available to use are model 49, model 80 and model 198. There is also a model 158 cylinder which could probably be fitted to one of the model 49/80 motors to make it look right.
The motor that came out of the frame (model 159 I think) is available but would cost a lot to bring out from the UK (freight cost alone is $620).

Greg Harding wrote:Likewise, if you have a rolling frame or frame 125, 158, 159 or 198 then I may have your motor or cases and we need to talk. Sorry Graham, there is no 199B motor.

Hi David, do you remember that I have motors that don't have a matching frame? It would be a shame to break a pair if that was what you were thinking?

Greg Harding wrote:Likewise, if you have a rolling frame or frame 125, 158, 159 or 198 then I may have your motor or cases and we need to talk. Sorry Graham, there is no 199B motor.

Hi David, do you remember that I have motors that don't have a matching frame? It would be a shame to break a pair if that was what you were thinking?
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Greg the frame is a Sammy Miller made in 1975. The motor that came out of it is still in the UK and the original frame probably is too.
I'm after a big-crankwheel 325 or any 250 Sherpa T motor with boot-heel casings and square finning to match the era of that frame. Model 125 is a small-crankwheel 325.
I don't want to break a motor/frame pair.

David Lahey wrote:This is to show how much of the side panels need to be trimmed back

Hmm, it needs a fair bit of trimming doesn't it.
I don't mind the 75 style alloy tank, but the one that was on it looked rather agricultural with the cutouts for the top shock mounts. It just doesn't look like it suits the SM frame.

For what its worth I wonder if cutouts on the slimline one might have a similar effect.
You could try 'blacking out' (or greying out) what needs trimming to get some idea of what it might look like.

Or would it be worth considering a '76 style tank and try some separate sidepanels of your own design to suit the frame?

Motor-wise, I'd go with Greg's suggestion.