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Looking for one of these late model engines. Prefer new
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Parts Wanted K/B 3.5 drum motor
- Thread starter NAMBA860
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Shane, can you post a reference pic?
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Found
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I was curious to the rarity of the drum rotor K&B 21? Was performance increased with the drum rotor? Back in the day front rotor 21's were all that was available.
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The original .21’s didn’t have a disk or drum intake rotor they used the outboard intake and side mounted it and fuel was distributed through a slot in the crankshaft
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I have a NIB drum motor.. I can take pictures and provide info if needed
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How much?
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I don't charge for info and pictures... bahaaaaaa. (the motor is not for sale).. sorry for the confusion.
Grim
Grim
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No problem I bought 5 used ones at the Namaba nats yesterday for $100
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When I first started running in the early 70's all we had were Veco 19's. The Taipan came out but they were subject to crankshaft's breaking although a little better than the Veco. And then the front carb K&B' and right after was the OPS 3.5. The advantage with the OPS was the carb and the tuned pipe and they ran pretty good. I bought a Picco 3.5 and the piston and cylinder weren't a good match with no compression. I was told Picco had a problem with the fitment, but I pretty much stopped running so never replaced the piston and sleeve. Now I have a new Picco that needs a piston and sleeve.
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Yup, those old OPS 3.5 side port motors would run forever… my first mono had an OPS in it and I won a ton of trophies with it… I even ran it at the IMPBA nat’s in 1988.
The piston and sleeve were so loose I could push the piston all the way out of the top of the sleeve.. but it still ran good.
get a little heat in it on 50% and it ran great..
I’m currently in the process of building a nostalgic version of my first one..
White and yellow .20 Husselcraft with a NIB OPS .21 side port. Two blade X440 prop.
May even put my Futaba square box wheel radio in it on channel 80.
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Could you tell me if the one you have has the thin head button for short plugs or the thick head button for long plugs. I bought a box of 5 used engines at the nationals last week and the engines had both types. I was wondering what they came with out of the factory. I always thought the early version with the intake on the side took short plugs and the new drum rotor version took long plugs.
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I am SURE.. i can double check.. the thicker head button. (13mm motor) the 12mm motors (Short head button) the cases are not interchangeable with the 13. If you pull the head off and the liner is notched for the head bolts.. its a 12mm (others help correct me if you have more info)
Grim
Grim
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I have little knowledge of the LONG vers SHORT plug heads.. but that might be a thing. Just not sure about the 12 to 13 head buttons
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