source of vibration?, car vibrates at ~ 3k RPM Options

[astronomerdave]

My 914 was converted to an electric vehicle; other than having an electric motor instead of a gasoline engine, the drivetrain is the same as you're familiar with. The electric motor has a hub adapter which matches the bolt pattern of the original flywheel. Then I'm using the orig flywheel, clutch, and transmission. The problem is that somewhere around 3000 RPM the car starts to vibrate (and gets worse with increasing RPMs).

Now at least two or maybe three other guys who did this same conversion had similar vibrations and all of them found that they had troubles with their transmissions. So I jumped to conclusions and thought the same. But I just discovered that I get the same vibration whether driving, sitting in neutral, or sitting with the clutch disengaged.

I have my own new theories now but want to hear what some of you other people think.

Thanks,
Dave

p.s. images of the car, including some parts such as the motor, flywheel, etc. can be found here: http://www.halestorm.us/evconstruction.htm

[yeahmag]

Dave,

I just sent you an email without reading this thread first. This is very unlikely to be a transmission problem if the vibration occurs while in neutral *and* not in motion.

Per my email, you need to check the pressure plate/flywheel/adapter both for alignment, proper assembly, and for balance as an assembly. Now that you have mostly ruled out the trans this should be a failrly easy problem for a machinist to diagnose. This is not something you can "eye ball" like some of those EV guys were talking about on the EV Google thread.

Yank the motor and take it to one of the guys on campus, Hollywood Machine in Pasadena, or my favorite - John Edwards at Costa Mesa R&D. Tell any of them Aaron sent you!

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