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Old 10-02-2009, 02:30 PM   #1
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Default Gear mesh problem with Mugen MBX5-T, engine is too far forward?

I have a Mugen MBX5-T with a Picco P3-28, and I am having some gear mesh, or better said "clutch bell position" issues. I can get the gear mesh set properly, however the spur/clutch bell teeth mating position is off. Basically, the engine sits too far forward, and the spur gear has a couple millimeters of the teeth not contacting the clutch bell, and the spur is very close to the bell itself. I am using a BCE chassis, and I dremel'd it a bit to move the motor mount back some, but it hardly helped. I also have to clutch bell shimmed as close to the flywheel as it can be without rubbing the flywheel pins. Anyway, the biggest problem about this is that it's starting to mess up the teeth on the clutch bell and spur gear. I cant seem to find a clutch bell that has the teeth machined right against the bell, which I think would almost solve my problem. Do Picco's just have a long crank and I would be better off to switch engines? Has anyone else had this problem? How did you fix it? And does anyone know of a company that makes an adjustable motor mount (allowing the engine to slide forward or backward) for the MBX5-T, or a motor mount that is adjustable from another vehicle that uses the same hole pattern that the chassis has? (I tried my OFNA ones and they don't work)

Anyway, thanks for any suggestions or help!
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Old 10-02-2009, 02:49 PM   #2
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Check to make sure the flywheel is seated as far back on the crankshaft as possible.

Sorry, that's the only advice I have. Kinda new, dunno the difference in motors/clutchbells yet.

Hmm, actually, I think Kyosho's have a more shallow clutch bell than some other cars. Not sure if that means changing the flywheel and everything or what though....
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Old 10-02-2009, 03:00 PM   #3
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What kind of shimming did you have to do to get the screw on the end of the crank shaft? Assuming that the crank is "normal", when you put the brass collet, fly, fly nut, shims, bearing, clutch bell, bearing, shims, then screw/washer on the end, it should be close. How far off are we talking? Can you post pics? If you used the shimming your manual suggested for the clutch bell assembly, perhaps your spur is on the center diff backwards? If the shimming was way off, perhaps your collet is wrong?
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Old 10-02-2009, 03:11 PM   #4
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Quote:
Originally Posted by noR View Post
Check to make sure the flywheel is seated as far back on the crankshaft as possible.

Sorry, that's the only advice I have. Kinda new, dunno the difference in motors/clutchbells yet.

Hmm, actually, I think Kyosho's have a more shallow clutch bell than some other cars. Not sure if that means changing the flywheel and everything or what though....
It's as far back as it can go.

Quote:
Originally Posted by Razathorn View Post
What kind of shimming did you have to do to get the screw on the end of the crank shaft? Assuming that the crank is "normal", when you put the brass collet, fly, fly nut, shims, bearing, clutch bell, bearing, shims, then screw/washer on the end, it should be close. How far off are we talking? Can you post pics? If you used the shimming your manual suggested for the clutch bell assembly, perhaps your spur is on the center diff backwards? If the shimming was way off, perhaps your collet is wrong?
Well before I installed the engine, I shimmed it like I have the clutch bell shimmed on my other nitros, 1 or 2 shims behind and 1 or 2 in front of the bell, and there is a very tiny amount of play. But when I installed the engine, the CB was too far forward, so I removed the shims from behind the bell to set it back as far as possible, and it's just like it is now, with a couple millimeters of the spur off the CB teeth and close to the bell. I bought the truggy used, so it is a possibility that the spur is on backwards, I will have to look into that, I will also see if it is possible to shim the center diff forward a bit. And I am using the collet that came with my engine, and the flywheel I am using is an OFNA flywheel, which uses the same collet that comes with Picco engines.

I think the spur gear being installed backwards is probable here, and I will be sure to check that out.

I can't post pictures right now, but I will have access to a camera tonight and will post some pictures tonight.
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Old 10-05-2009, 11:47 AM   #5
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I just had a similar issue where i did not like how the clutch bell engaged with the main gear. I ended up trying different collets i had and the flywheel engaged them all a little differently. the teeth are almost dead center now.
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Old 10-05-2009, 01:37 PM   #6
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Are you using and actual mugen flywheel nut + collet + clutch bell. I have seen a few people (myself included the first time) try and use the HPI or some other similar cluch style nut. The mugen nut is shorter then most. I ran 1 small shim behind the clutch bell and the rest in front of it. And yes this is in my mbx5t with a BCE chassis as well. I also always used the 1 pice engine mount. Dremeling the holes is useless the BCE chassis holes are all in the correct location.
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Old 10-05-2009, 03:41 PM   #7
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awdcameolsx is on the right track.. you will need a Mugen Fly Wheel and nut.. The flywheel is narrower than an OFNA, and the nut is considerably shorter as well.. I tried ot put a Mugen flywheel on a Jammin, and it had the opposite problem of what your describing..
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Old 10-05-2009, 05:39 PM   #8
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I have to agree with the others, I ran a 5t with a BCE chassis before moving to the 6t and I ran a rossi p5 and a picco 26 in it using a mugen fly wheel/collet and a ofna vented bell with out the problems you are describing.
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Old 10-05-2009, 05:43 PM   #9
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Opps I did mean to say flywheel and not clutchbell. I have used ofna clutch bells they work fine. But the flywheel, collet, and nut should be acutal mugen.
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