Overvolt Crystalyte

I haven't do it personally, but you might want to check out www.endless-sphere.com/forums.

In short; yes. Major yes. In fact, no one has EVER managed to fry one, and several members are running well over 100V on them with no problems. 45mph is easily doable with a Crystalyte.

This is assuming you are referring to an X5, of course. The 4XX motors are robust (they will tolerate 72V without issue), but they don't come close to an X5.

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Any idea how much I can overvolt the controller for a Crystalyte RoadRunner 4820?

The RoadRunner is a 408 motor, one of the 4XX line. 72V has been tried with good results before, but I don't think anyone has gone much higher than that. 72V will give similar performance to an X5 at 48V.

I don't think the controller will take much overvolting. You could take it apart and check a few parts to see what it could take if you want.

Would be a good idea to upgrade it with 4110 FETs, IMO. It's very cheap to upgrade a brushed controller (I did it for less than $10 on my YiYun controller) and not too hard if you have a little skill with a soldering iron.

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(((cheap to upgrade brushed controller)))

... "roadrunner" is a name that is being used for brushless motors/controllers.

http://www.evdeals.com/HubRoadrunner.htm

can the X-CT3640 be over volted to 48 volts it is the phoenix controller on http://www.electricrider.com/crystalyte/parts.htm and it is about $50 cheaper than the 48 volt one.

and what fails when a controller fries because of over volting?

Ugh, they need to stop using these weird names. It's confusing meh. :/

The FETs and caps are what almost always fail. The gate drivers and voltage regulators can fail, too, but that doesn't happen often. Other stuff can fail, but it's very rare to see that happen, and it's usually due to a quality control issue.

The author of this post isn't responsible for any injury, disability or dismemberment, death, financial loss, illness, addiction, hereditary disease, or any other undesirable consequence or general misfortune resulting from use of the "information" contained herein.