Forcing a 550 can Holmes motor in a VFD

[Druxus]

Didn't know a 550 can motor doesn't fit a VFD transmission until it didn't fit putting the trans together. The Holmes trail master was 2mm to long, seems like a oversight on Vanquish part not to have a 550 fit but what ever. I decided to grind the back of the motor to see if it would fit since I didn't need that much more room. Hard to see in the pic but there is just a hair bit of space and the motor can be adjusted without any binding. Haven't run it yet so I'm not sure if there will be some hidden side effects.

[mjensen]

My favorite posts on RCC are the ones where people are solving problems created by manufacturers oversites. I hope it works out for you.
I went though the same issue with my VFD Capra build when I tried to put a Fusion motor in it which is 550 length. I ended up adding 10mm spacers to the standoffs between the VFD motor plate and the gearbox and making a 10mm longer top shaft out of 5mm chromoly rod. I only have pretty basic tools, no machinist stuff, and the only specialty tool I needed to buy was a v-drill guide for drilling the cross pin holes in the shaft and a M4 die for the threads on the spur gear end. With the extra space I can fit pretty much any 550 can motor now.
I apologize for the picture. For some reason it's getting rotated when I post it here.

[Druxus]

Originally Posted by mjensen

My favorite posts on RCC are the ones where people are solving problems created by manufacturers oversites. I hope it works out for you.
I went though the same issue with my VFD Capra build when I tried to put a Fusion motor in it which is 550 length. I ended up adding 10mm spacers to the standoffs between the VFD motor plate and the gearbox and making a 10mm longer top shaft out of 5mm chromoly rod. I only have pretty basic tools, no machinist stuff, and the only specialty tool I needed to buy was a v-drill guide for drilling the cross pin holes in the shaft and a M4 die for the threads on the spur gear end. With the extra space I can fit pretty much any 550 can motor now.
I apologize for the picture. For some reason it's getting rotated when I post it here.

Great job on extending the transmission!

I went on a 3.5 trail run with it today without any problems with the motor, so I'd say that grinding the back off will be ok.

[twade984]

So I can say that if you remove the red cap off the fusion, and trim a small piece of ribbing on the vfd, it will fit in there no problem.

[mjensen]

Originally Posted by twade984

So I can say that if you remove the red cap off the fusion, and trim a small piece of ribbing on the vfd, it will fit in there no problem.

I had heard that but there is one component of the motor controller that looks to have a thermal pad on it and it rests against the aluminum end cover. I assumed the cover was acting as a heat sink to help cool the electronics and with reports of the Fusion running warm I was afraid that removing the cover might make it run hotter. Maybe that's not the case.

[mjensen]

Originally Posted by Druxus

Great job on extending the transmission!

I went on a 3.5 trail run with it today without any problems with the motor, so I'd say that grinding the back off will be ok.

That's great that it worked out. The simplest solutions usually turn out to be the best. I have a bad tendency to overthink things and end up making problems worse.

[twade984]

That could be the case, and that solution obviously doesn’t help if you want to run most any other 550 length motor. I agree with you guys, seems a real shame they didn’t design in a little more room...

I’ll report back if I overheat... I’m pretty easy on stuff, so I’d be surprised if anything happens. But you may be right.