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Short Stroke BMW engine with San Jose frame and re-enforced swing arm.

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Joined: Thu Dec 27, 2012 9:42 pm
Location: Buda, TX

Short Stroke BMW engine with San Jose frame and re-enforced swing arm.

Post by winsur4 »

Back in 2014 I put a BMW in storage for Delton Shirley who lived in Midland Texas. He purchased a BMW basket case that came with a short stroke racing engine that most likely was built by San Jose BMW. It is not a B&S engine, but one that was based on the design. The engine is a 1050cc short stroke. Delton had Parkinson's Disease, and I helped him sell all his motorcycles but this one. He passed away last week, and I decided to try again to sell this for his widow. The below link has the story of this bike I put on Motorcyclist Cafe back in 2014."
http://www.motorcyclistcafe.com/forums/ ... ht=winsur4
I did a lot of research back in 2014. Here are some things I came up with:
From Delton and people I contacted via phone or email:
1. The short stroke 1050CC assembled engine and a basket case based on many R90 parts with a San Jose reinforced race frame and swing arm were advertised in the BMOA magazine classified adds sometime in the 1990s. The engine race frame and reinforced swing arm were originally purchased from San Jose BMW as was the engine according to the add. The rest of the parts in the basket case were an R90S type fairing with R100 controls. The phrase "Pridmore engine" was either in the add or told to Delton when he inquired about purchasing the bike. Delton believed the add said the engine was built by San Jose BMW.
2. I contacted Reg Pridmore, and sent him pictures of the engine an assembled bike. He was pretty sure it is not an engine he built. I think Pridmore's name was associated with the ad only because it was similar to the B&S engine used in the Superbike Races. There are 2 differences that I noticed: 1. The intakes are not splayed outward. 2. There is a different oil cooler feed pickup.
3. I also talked to Chris at San Jose BMW. He could not recall the transaction or anything about this BMW. Delton had talked to Chris at the Paonia BMW rally sometime in the 1990s, Chris was familiar with the engine at that time, and gave Delton instructions on how to start it. He warned Delton that the high compression, required Avgas, and a car battery to start it. At the time Chris was interested in purchasing the engine, but Delton declined the offer. 20 years later, Chris did not recall the encounter with Delton.
4. I contacted Dean "Grandpa Hoon" Lear the former owner of San Jose BMW on the Motorcyclist Cafe. He gave me a history lesson, and names of people to contact, but was not sure about the origins of the engine.
5. From Delton: The original BMW MOA ad stated that the engine was purchased from San Jose BMW. The owner from whom Delton purchased was possibly Mark Brightwell, a well know knife maker and artist from NW Austin TX. He passed away in 2002 of melanoma skin cancer. He lived in Leander TX which is where Delton purchased the motorcycle.
6. The basket case was assembled in Lubbock Texas by former BMW dealership owner Ray Randolph. Best know as a Million Mile BMW rider, and builder of 10 Gallon gas tanks for Perry's Side Cars in Fort Worth. I knew him as a member of the Tall City Road Riders in Midland Texas. After assembly, Ray started it using the instructions Delton got from Chis at the Paonia Rally. It was tested at a private airport in Lubbock. It was very fast, but not street ridable.
1974 R90S
1976 R90/6
1961 R50 Sidecar (R100 motor)

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