Here is a video about the history of my family's 1942 side-car motor bike, and it's recent modernization to a new engine and improved transmission method. I thought this might be of interest to the participants on this forum.
1942 sidecar motorbike modernization project
- Thread starter rgp1942
- Start date
Welcome to the forum and thank you for sharing your family heirloom with us. If the kids who the bike was built for knew how cool they would be today they would have forgotten about horses. I would guess there was more than a little envy amongst their friends when it was new.
Nicely modernized. Thank you for the video.
Steve.
Nicely modernized. Thank you for the video.
Steve.
Thank you. I had to solve a lot of "engineering" problems, but at the same time it was fun.
BTW - something that would be if interest to folks on this forum - I watched several YT videos about installing a Series-30 Torque Converter on a 79cc Predator engine with a 5/8" shaft. All of them left something out. When I installed as they said, the drive pulley end put excessive pressure on the engine output shaft bearing. I could hardly pull the engine over. Also the rubber seal was damaged. I finally figured out that a sturdy washer with an exactly 5/8" bore (make your own) needs to be put on the engine shaft, against a small shoulder there, BEFORE putting on the spacer/collar that converts the shaft from 5/8" to 3/4". After this everything went fine. Bottom line, if you don't put this stop washer (not provided) on you will damage the engine. This stop washer is shown in my video, along with a screw collar that is also needed to prevent the spacer collar from slipping and the keys loosing purchase. Also, the 20 foot pound torque on the pulley nuts and bolts is way excessive. Doing this will also cause damage. Use red locktite liberally instead. I now have about 4 hours on the upgraded bike with no problems - runs great. The torque converter belt is not wearing/shredding at all. I love the Predator engine -- starts on first pull every time and idles nice and low with no engagement of the CVT - choke it - pull it thru twice with ignition off, then ignition on and it starts on first pull at idle - does not need to be at mid throttle.
BTW - something that would be if interest to folks on this forum - I watched several YT videos about installing a Series-30 Torque Converter on a 79cc Predator engine with a 5/8" shaft. All of them left something out. When I installed as they said, the drive pulley end put excessive pressure on the engine output shaft bearing. I could hardly pull the engine over. Also the rubber seal was damaged. I finally figured out that a sturdy washer with an exactly 5/8" bore (make your own) needs to be put on the engine shaft, against a small shoulder there, BEFORE putting on the spacer/collar that converts the shaft from 5/8" to 3/4". After this everything went fine. Bottom line, if you don't put this stop washer (not provided) on you will damage the engine. This stop washer is shown in my video, along with a screw collar that is also needed to prevent the spacer collar from slipping and the keys loosing purchase. Also, the 20 foot pound torque on the pulley nuts and bolts is way excessive. Doing this will also cause damage. Use red locktite liberally instead. I now have about 4 hours on the upgraded bike with no problems - runs great. The torque converter belt is not wearing/shredding at all. I love the Predator engine -- starts on first pull every time and idles nice and low with no engagement of the CVT - choke it - pull it thru twice with ignition off, then ignition on and it starts on first pull at idle - does not need to be at mid throttle.
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Feel free to share as desired. That's why I made it. And thanks for the feedback.
Very cool bike!!! 
I have to admit... I was a little sad to see all the original parts (that had survived for so long), being replaced with those Chinese parts.
I have to admit... I was a little sad to see all the original parts (that had survived for so long), being replaced with those Chinese parts.
I appreciate the tip on the 5/8 washer to protect the seal... I'm collecting parts for a 79cc build and about the only thing left is the 30seres... I really needed to see this thank you?
This steel machinist washer is 5/8 I'd and they come in different thickness... It would serve the same purpose as brass but not compress over time... And can be used on the driven side of the TAV...
Your right about a regular washer there also not completely flat...
This steel machinist washer is 5/8 I'd and they come in different thickness... It would serve the same purpose as brass but not compress over time... And can be used on the driven side of the TAV...
Your right about a regular washer there also not completely flat...
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I struggled with that myself. I wanted to maintain as much provenance as I could. With the bike and I both turning 80 I thought I could give it a new life to live on into the future, whereas I can't! My grandkids really appreciated it, and maybe theirs will too!
I was hoping someone would benefit from this tip - is why I put it in the video. A 5/8" bore washer from a hardware store is not really 5/8". I used a thick brass washer I already had and reamed it out. It needs to be an exact fit because the shoulder on the PTO shaft is not very big. After figuring out that this needed to be done, I wondered how many people who watched the half-dozen YT videos I did ruined their engines. BTW, the Torque Converter I used was IPARTS EXPERT from AMAZON. The bolts holding the TC to the engine were too long and had to be cut down. Also, one of them stripped out so be careful on tightening. Seems like there were other issues but my memory is now short! I turned the bolt holes in the TC into slots so I could twist the TC to tighten the chain (there was no room for any kind of chain tensioner). Good luck with your project.