Bonanza Mini Bikes ID????"
- Thread starter buckyten
- Start date
BC is the early bikes, with solid fork plates with an ID badge riveted on it.
MB is the later bike, open forks with a serial plate on the front of the engine plate.
MX bikes used fiberglass tanks and seats and 8" wheels and sometimes sported a 2-stroke Hodaka engine. They were designed to compete with early motocross bikes of the era, hence the MX designation
There are exceptions to these guidelines and some models that crossover between them. For example, the BC 1400t used the fiberglass tank and seat, but still had the 6" wheels
MB is the later bike, open forks with a serial plate on the front of the engine plate.
MX bikes used fiberglass tanks and seats and 8" wheels and sometimes sported a 2-stroke Hodaka engine. They were designed to compete with early motocross bikes of the era, hence the MX designation
There are exceptions to these guidelines and some models that crossover between them. For example, the BC 1400t used the fiberglass tank and seat, but still had the 6" wheels
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Just a guess but common sense would say the BC may have came from Bonanza cycle and MB came from Mini Bike. Bonanza made karts first and then started to make bikes too, it was probably an easy way to decipher parts/models between the karts and bikes.
The "BC" line of bikes were 1" tubing and larger overall, In 1969 they came up with a chopper (designated as "CR"), a very small bike they called MB-200 that had 4" wheels, and a bike seen listed as both MB-250 and 300 (they 1969 parts list shows it as a 300)-that was the beginnings of the "Scout" division of bikes. Those were built from smaller 7/8" tubing, shortly after that they started on the larger MB and MX line which were 7/8" tubing as well. Like the BC series bikes, they were based off the same basic frame design only configured differently as per model setup
"MB" versions, other than the little 200, were 6" wheeled and either non suspended or external sprung type suspension, a little more recreational.
"MX" versions while built off the same frame but featured a more heavy duty fork that was internally sprung and 8" and even a 10" wheeled version.
The "BC" line of bikes were 1" tubing and larger overall, In 1969 they came up with a chopper (designated as "CR"), a very small bike they called MB-200 that had 4" wheels, and a bike seen listed as both MB-250 and 300 (they 1969 parts list shows it as a 300)-that was the beginnings of the "Scout" division of bikes. Those were built from smaller 7/8" tubing, shortly after that they started on the larger MB and MX line which were 7/8" tubing as well. Like the BC series bikes, they were based off the same basic frame design only configured differently as per model setup
"MB" versions, other than the little 200, were 6" wheeled and either non suspended or external sprung type suspension, a little more recreational.
"MX" versions while built off the same frame but featured a more heavy duty fork that was internally sprung and 8" and even a 10" wheeled version.
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They sold a version that was tankless, it was in the 1300 line, I want to say it was referred to as a "1350" as I have seen that in some newspaper dealer advertising. But there was no photo verification and they only list the BC1300 on the factory 1970 price sheet, no in betweens listed, so I don't know if it was a Hybrid model or possibly what the 1300 became in 1970 (BC bikes start to drop off at that time)
This bike I bought and used for parts was a later built 1969:
Bonanza BC's are not Torque converter friendly in their stock configuration and would need some creative installation to be done. Bonanza did offer some models post 1970 with taller jackshaft/swingarm plates to accommodate the driven units for TC's but are not as common to see and I am not sure if the BC line ever got them like the MX/MB frames got. There were briefly some repop tall brackets being produced but not sure if they are still available.
This bike I bought and used for parts was a later built 1969:
Bonanza BC's are not Torque converter friendly in their stock configuration and would need some creative installation to be done. Bonanza did offer some models post 1970 with taller jackshaft/swingarm plates to accommodate the driven units for TC's but are not as common to see and I am not sure if the BC line ever got them like the MX/MB frames got. There were briefly some repop tall brackets being produced but not sure if they are still available.
I doubt that they have anything other than what the 2 stroke version Bonanza's used in stock, which was for a larger 40/41 pitch chain. They are closer in diameter to a 60 tooth 35 pitch that was stock on that particular model, so you could upgrade to the larger chain, but of course need a sprocket as well for the jackshaft.
Dave miller concepts in California might have repro sprockets, and new old stock ones do still pop up on ebay pretty regularly. Bonanza used a sprocket/drum assembly made by Bendix (or a copy of one in the later years) 5" drum area for the brake, so dont limit your search to Bonanza only if you have to go that route. The bolt circle on them is 3.25" pattern. you will see them with three and six mount holes in the center, both work fine for replacement as Bonanza only used 3 mount bolts to attach to the wheel. again if your bike was the model like I had it was 60 tooth count, 35 pitch.
Dave miller concepts in California might have repro sprockets, and new old stock ones do still pop up on ebay pretty regularly. Bonanza used a sprocket/drum assembly made by Bendix (or a copy of one in the later years) 5" drum area for the brake, so dont limit your search to Bonanza only if you have to go that route. The bolt circle on them is 3.25" pattern. you will see them with three and six mount holes in the center, both work fine for replacement as Bonanza only used 3 mount bolts to attach to the wheel. again if your bike was the model like I had it was 60 tooth count, 35 pitch.
I hope you don't mind me piggy backing on this string. I recently bought a mini bike to restore, turns out its a Bonanza frame. The frame label is riveted to front of the frame, Made in San Jose, Calif. BONANZA and has serial number of 06039. This plate is in good shape. Curious if the # will tell me what type of model I have or not? Appreciate any feedback. Regards,
Yes, that is the exact style of tag on this frame. So....I don't think the forks on this bike are original but not sure. They are just like the front shocks on the Mini Bike Mike you tuber who is restoring a Bonanza with his Dad. The shocks are the 12 inch version, kinda beefy ones. I need to figure how to send my cell phone photos so I can share them here. I don't know how at this point.