ISDT Engine.

[Dale Fisher]

This one may go out to Paul or Doug.  I'm working on cleaning up an ISDT engine for possible auction.  Per a previous post the number etched into the green marking didn't indicate where and when it may have been used.  The cases are also stamped with "S7" would this indicate anything special? I'm reasonably sure the head is not orginal since it is not cut and does not have a matching drill hole for the seal to the cylinder.

[Paul Danik]

Dale,

I need to look and see exactly what is stamped on my 73 ISDT engine cases, I am pretty sure that it is 73ST and then a number. I will try to look at them tomorrow.  Also, is there a hole in the engine case fin where the engine would have been wired and sealed to the frame?  It would be in the fin area near the front of the engine cases.

Also, I think that the SACHS name was removed from the engine side covers on our bikes and the PENTON decals were installed, along with the "special KTM tuning" decals.

I have some stuffed engine cases that came from the Penton R&D department, they have S10 stamped on them and the aluminum oil filler plug has an X stamped into the top of it, that is how they kept track of who had what and what was done to it....  Those cases are machined out to locate and hold the horseshoe shaped aluminum stuffing ring, maybe your cases are stuffed?


Paul

[firstturn]

Dale,
  This engine appears to be an "A" engine with the sunburst head(not cut for an up pipe), cylinder that is cut for a side pipe (1970/71 Penton or other brands of bikes with Sachs engines) and the single hole fo the ignition wiring.  You didn't mention if it was a 5 or 6 speed. I have had several of these "A" engines with similiar pain that I was told they were used in Qualifiers?  Just my input.  I will turn it back over to Paul or for someone else to have input.

Ron Carbaugh

[Paul Danik]

Dale,

   I just checked and my ISDT 125 is stamped ST 73, not 73 ST as I mentioned before.

   The stuffed cases that I have are stamped S 10 just above the top rear motor mount on the right engine case, I am starting to think that your cases were possibly part of the same batch that the Penton R&D department produced, most likely under the direction of Ted Penton. I have no idea if Penton ever used those stuffed cases in any of their early ISDT machines, maybe Doug might remember.  But, if you find a hole for a sealing wire in your cases that would give weight to the idea that your engine was used in an ISDT machine.  Have you looked for any markings in the ignition area, possibly on the flywheel?

   If you ever pull the top end you can look down into the lower end and see the aluminum stuffing horseshoe quite easily.

   There certainly should be a few ISDT engines around as most of the guys I have talked to never kept their bikes, they are out there some where.

   Even if your engine wasn't used in an ISDT, it is still quite possibly a real find as I am sure that those cases were not just handed out to just anyone.

Good luck, hope this helps.
Paul

[Dale Fisher]

Oil fill plug is stamped with an "x".  The Monoplat has a green stain marking.  The left front of the engine has two small holes drilled for seal apparently for attachment to frame just below bolt hole. I vaguely remember something being special about the interior but thought it was transmission related.  Side cover tag reads 6724208 1251/6A.  The stamped S7 is located just behind the clutch cable entry hole and in the darkened area just above the top rear mouting.

[Doug Wilford]

The paint markings on the engine are from one of the qualifiers.  Most of the clubs that put on the qualifiers did not mark all the parts that were marked at the six days,   The aluminum horseshoe that Paul has is one of maybe 6.   These were used as tests on the "A" engines to help performance.   Sachs soon made the "B" engine
with the stuffed cases.   These horseshoes were made by hand, Ted Penton did all the machining and design.  The first one was fit in the cases so good that it had more down compression than up.   With more machining giving more clearance the first one ran like a top.
At the time Pentons R&D test area was across the street in a large vacant parking lot, and a High bridge across a river that had about 1/4 mile incline.  Enough of an incline that proper jetting was needed to prevent seizing when wide open up or down. (It wasn't to far of a push back to the shop)  The aluminum ring worked okay for moto-cross but starved the bottom end, rod bearing failure, in enduro conditions.   One reason why Penton did not use the Sachs "D" engine bottom end.

[Paul Danik]

Thanks Doug, that is some pretty interesting information.

Dale,

I checked the fins on my cases and they are not drilled for a sealing wire which means that yours were most likely drilled for a specific event.  I do not remember having my engine wired to the frame and sealed at any qualifiers, only at the Six Days. My guess is that the only two non ISDT events that might have done that type of sealing would have  been the Corduroy or the Berkshire events.  Hopefully someone with this knowledge will step in, Doug, Speedy,Al Born anyone???

Paul

[Paul Danik]

For those who like a good mystery to solve this engine is proving to be very interesting.

Today I had the extreme pleasure of meeting Dale Fisher in Ohio and completing a deal with him to acquire the engine. Dale had a scrap book with him that was very interesting, especially the pictures of him visiting Eric Cheney's shop in England as a teenager, as well as many race photos of he and his family.

 Dale has had this engine for many many years and he said he remembered that it was special and he is pretty sure they bought it from Penton Imports.

The engine markings S 7 and the X stamped on the top of the oil filler plug match the engine that I have that is stamped S 10.  These engines have an aluminum horseshoe installed in the crank area, as explained by Doug Wilford in his post.  Doug explained how Ted Penton did the design and machine work on these engines.

The next items of interest are the paint markings on the engine and ignition flywheel.  In one of the markings, 65 is scribed into the paint, as can be seen in Dale's first picture.  Another interesting feature are the holes drilled in the lower engine case fins at the front of the engine.  

From what I know only at the ISDT were the engines wired and sealed to the frame.  Also to the best of my knowledge, only at the ISDT were there so many engine parts marked with paint, and most interesting is the number 65 scribed into the paint mark, at the ISDT the scribed number would match the rider number.  The idea was to be able to see if anyone switched engines.

When I arrived home I immediately started to search for a clue as to who might have ridden at the ISDT as number 65 on the US team on a Steel Tanker. I found the answer in a piece of Penton literature, it was Jack Penton in Spain, 1970.  

IS this for sure Jack's engine from Spain in 1970, most clues point to that conclusion, but more research is going on and we will for sure have an interesting time looking over this engine at the next POG meeting.  Hopefully this engine with give Jack something to build a replica of his 1970 ISDT machine around.

Thanks again Dale.

Paul

[Steve Minor]

What a great story Paul....and what a great find!

Good Job!

Steve Minor
Wilmington, NC

[Charles Gresham]

Dale's scrapbook documentation is amazing. I had the privilige of looking at it at 2009 VMD.

[Paul Danik]

Upon further examination last night a third hole was found in the cylinder fins.  The first two are on the top fin, one on each side as is customary for sealing the cylinder to the head at the ISDT.  The third hole is in the bottom cylinder fin and lines up with the two holes that are drilled in the fin on the bottom end of the engine.  This explains why there are two holes in the bottom end fin, one for sealing the engine to the frame and a second one for sealing the cylinder to the bottom end.

Another interesting feature was also found, as was mentioned before the engine case and clutch cover are stamped S 7, a matching S 7 stamping was found on the top of the cylinder just in front of where the head gasket would sit, in the area that would be above the exhaust port.

The only picture that we have of Jack on his 1970 ISDT machine is in a piece of Penton literature that features Jeff airborne on the cover on his 1970 ISDT Penton. The caption under Jeff's picture says,  SPAIN ISDT "70" .  If anyone can dig up any pictures of Jack's 1970 #65 ISDT machine it would be greatly appreciated. Actually any pictures of the guys listed below at the 70 ISDT on their machines or just pictures of their bikes would be appreciated.

In 1970 Jack joined his brothers Jeff and Tom, along with Doug Wilford, to make up the USA Vase "A" team, they finished fifth with two Gold and Two Bronze medals. This was Jack's first ISDT.

Paul

[Admin]

Here are pictures of Paul's engine in question: