Exploding Governor
- Thread starter FatBuddyCat
- Start date
I think you should go for what you are trying to do.
Just start off with a rod and flywheel, governed with ALL original linkage. I have an engine set up this way. I have a TAV and I'm set up to where my governor does nothing at top speed full throttle. (Some would say "Why you knucklehead?"). It may only react if the load changes like starting up a hill from a flat road at the same throttle position. I can do this but would switch back to the jackshaft for lower speed higher RPM.
I would get a tach on the bike and start out with the throttle spring one hole closer to the blower housing on the governor arm. Then adjust the throttle screw to see what RPM the governor reacts at. If that isn't enough then drill a hole further out on the governor arm and try again. You may end up pretty far out on the arm with the throttle spring to get near 5K RPM. The nice part is all this can be reversed easily. With the jackshaft and throttle screw alone I can govern my bike to at least 4500 without changing the throttle spring position.
Others have spun the governor gear way higher than 5K. I watched a video the other day where a guy was 7K+ with the governor gear still in place. I doubt it would break at 5K.
Just start off with a rod and flywheel, governed with ALL original linkage. I have an engine set up this way. I have a TAV and I'm set up to where my governor does nothing at top speed full throttle. (Some would say "Why you knucklehead?"). It may only react if the load changes like starting up a hill from a flat road at the same throttle position. I can do this but would switch back to the jackshaft for lower speed higher RPM.
I would get a tach on the bike and start out with the throttle spring one hole closer to the blower housing on the governor arm. Then adjust the throttle screw to see what RPM the governor reacts at. If that isn't enough then drill a hole further out on the governor arm and try again. You may end up pretty far out on the arm with the throttle spring to get near 5K RPM. The nice part is all this can be reversed easily. With the jackshaft and throttle screw alone I can govern my bike to at least 4500 without changing the throttle spring position.
Others have spun the governor gear way higher than 5K. I watched a video the other day where a guy was 7K+ with the governor gear still in place. I doubt it would break at 5K.
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See, thats the kind of spirit I was looking for! I was just thinking about the rod thing too and leaving the governor. I watched a few videos of destroyed internals from rods breaking but not governors. I built my Hisun 196 out with a cs grind cam, billet rod, 22 pound springs, 14cc head, PVL flywheel w/ 4 degree key, carbs, jets, header.....all that and more. I had it on a ct200u with a tav2 and I'd max that thing out, bind the belt and stop acceleration in a hundred feet or so. It went about 40 real quick but that was all the torque converter was gonna handle. I got rid of it with a Predator, added a box stock clutch and put on my DB30S. Dang doodlebug was so fast I had to split sprocket her and gear down. Now its a blast! Im going with the rod and keeping the governor, thanks for the great insight brother!
I remember your comment in a youtube video. You put the pred on to sell it and you kept the Hisun.
I would bet that my suggestion will work. I was afraid to comment at first thinking it might break forum rules. But I did say start with a rod and flywheel which means billet rod and RPM safe flywheel.
I would bet that my suggestion will work. I was afraid to comment at first thinking it might break forum rules. But I did say start with a rod and flywheel which means billet rod and RPM safe flywheel.
Yup, that was me. Nobody wanted to pay for the sweet 196. I actually prefer the Hisun over the JiangDong JF200 I built for the Trailmaster Storm 200. I love the quality of the Trailmaster but it doesn't boogie like DB30S. It could be the snowblower tires and heavy 420 drive train but that thing feels like it needs a torque converter to get going. Once she goes its off to the races but it takes a lot more to get there. Problem is that now I have another 196 that is over built for a Tav2. Sure I could put one on, wait for a juggernaut and tweak the pulley (or put a spacer in the driver to stay out of "overdrive ") but now we're talking a different exhaust to clear the frame on top of everything else for the Tav2. I kinda wish I had found my green doodlebug racer before I bought the Storm.
One other comment about this before I forget. I would bet that the Tillotson is able to govern at higher RPM because the throttle spring they use is slightly stronger of a spring than what you find on the Predator. If you could order a throttle spring from Tillotson you could avoid all the other testing I suggested.
Those throttle springs can be different. The spring on my Hisun engine had 1 extra coil compared to my old Harbor Freight clone. I'm using it on the HF clone that's on the bike.
Those throttle springs can be different. The spring on my Hisun engine had 1 extra coil compared to my old Harbor Freight clone. I'm using it on the HF clone that's on the bike.
I'm waiting for OldMiniBikes.COM they are my favorite supplier. I love those guys. When TheGreyGoay himself called me back and gave me some much needed guidance and help they had me for good. I had called a few other companies that honestly could care less. Same as to why I use Max Torque clutches, Jim Donovan himself reached out to me which really impressed me.
I few I called weren't very forward with answers to questions. These guys check in with me from time to time. I lost my Dad in February to pancreatic cancer and left Florida to stay with my Mom who has multiple myeloma. Its been a rough year, covid hasn't made it any easier. Ombwarehouse.com does. It's just a personal preference and I'm extremely loyal to those that help me.