crazy engine swap idea

[gotmuddy]

ive been looking for a 600-800 twin polaris motor to swap into my max IV for a few months with no luck. I got to thinking yesterday, why not swap a 5 speed atv chain drive engine in and get rid of the belt alltogether? Other than the need to shift gears on the atv transmission I dont see any real issues.

[maicolover]

I don't think the little clutch in ATV motor would take it!

[gotmuddy]

I don't think the little clutch in ATV motor would take it!

Well its a 5 speed so I could just select different gears. With the speed the input shaft spins on the trans there shouldnt be any slippage issues.

[hydromike]

Well its a 5 speed so I could just select different gears.

Would you operate the clutch and shift gears in the transmission by hand? If you're going to direct chain-drive the T-20, does the geometry work out that you can still put the engine above the transmission or will the engine case itself get in the way? Remember you'll have to hold the clutch in to shift gears on the T-20. Come to think of it, there would be a ton of hand-clutch work in any sort of technical terrain.

[gotmuddy]

Would you operate the clutch and shift gears in the transmission by hand? If you're going to direct chain-drive the T-20, does the geometry work out that you can still put the engine above the transmission or will the engine case itself get in the way? Remember you'll have to hold the clutch in to shift gears on the T-20. Come to think of it, there would be a ton of hand-clutch work in any sort of technical terrain.

I would mount a clutch lever on the left handle. I would only need to pull the clutch in to put in in reverse. all I use mine for is mud so I wouldnt be in anything too technical.

[Canadian_Zuk]

Why not just use a motor with a semi auto trans like a Honda Forman or something with an internal centrifugal wet clutch? You'd have 5speeds + reverse and no need for a hand clutch.

[gotmuddy]

Why not just use a motor with a semi auto trans like a Honda Forman or something with an internal centrifugal wet clutch? You'd have 5speeds + reverse and no need for a hand clutch.

I have thought about using a 300trx however I would have to make a custom sprocket since its a shaft drive. The reverse would never be used though as it would be incredibly slow.

[Canadian_Zuk]

I have thought about using a 300trx however I would have to make a custom sprocket since its a shaft drive. The reverse would never be used though as it would be incredibly slow.

True, but having both the T-20 and the manual transmission in reverse would give you a crazy low forward gear and that would be useful

prepare for a ramble lol

Depending on the rotation of the that TRX motor the drive shaft setup may be beneficial in fabrication as it would allow you to run a shaft and balance the weight side to side perfectly. With the chain drive your suck with aligning the new output sprocket with the T-20s fixed position. Motor mounting is another thing to consider, with the T-20 being rigid to the frame you would be best served to have the motor mounted with solid motor mounts if you plan on running the chain straight off the quad transmission or you'll probably toss the chain under load with rubber mounts. With a drive shaft you could weld an A-frame with pillow block bearings or something over the T-20 to support the upper sprocket and have those two chained together. Then it's just a matter of feeding that sprocket power via a drive shaft. This would allow you to lower the motor and push it to the center/right side and keep good U-joint angles and run rubber mounts. If you made the A-frame adjustable in height you would be able to swap out the sprocket sizes for fine tuning and keep the same chain size and engine location. This could be a bonus feature if you switch it up between tracks and tires.