Motobecane 50 engine installation

I removed the engine from my 1978 Motobecane 50VA.

I replaced the upper and lower motor mounts.

Lost the orientation of the bushings that go on the long bolt to connect to the frame.

Can't seem to get the lower mount to align.

Any advice or links to videos, can't seem to find any.

Cheers

Tim in Capitola,Ca

IMG_20201019_085500.jpg
IMG_20201019_085506.jpg

Re: Motobecane 50 engine installation

that spring should be on the inside of the hook, just loosen up bolts fight it and reposition.

Re: Motobecane 50 engine installation

Thanks, I knew that and had it that way after the photo. Do you know if it's just one bushing on the big bolt?

Cheers

Tim

Re: Motobecane 50 engine installation

Your ground will not work on that mounting bolt. The rubber bushing insulates the bolt from the frame. You will want to put that ground wire somewhere directly on the frame.

Re: Motobecane 50 engine installation

That ground strap goes from the pivot bolt to a terminal on the coil, so that is correct, but I usually replace it and tee it into the CDI, the stock braided thing is usually janky

Re: Motobecane 50 engine installation

Pushrod Fifty /

Ive done this on two Mobys, hope this helps. The left side upper mount shouldnt stick out from the frame any more than 2mm or the pedal will hit the variator while underway. Measure the head mounting with bushings installled in the head with a caliper and cut a piece of wooden rod that size to use a a gap measurement between the frame bushings. Put the bolt thru the bottom mount first and then the top one thru the head with the grounding ring terminal.

Re: Motobecane 50 engine installation

Thanks for all the help. Did get it bolted in with some twists and shouts. Will work up a better ground. Anyone know what that "arm" that's pointing down at the spring is used for?

Re: Motobecane 50 engine installation

That's a bracket that goes up to the stock bendy manifold

Re: Motobecane 50 engine installation

> Tim Clark Wrote:

> -------------------------------------------------------

2 spacer/bushings. order, bolt rubber mount, bushing, head bushing, rubber mount, nut.

was that the question? align to pulley or atleast eyeball it.

> Thanks, I knew that and had it that way after the photo. Do you know if

> it's just one bushing on the big bolt?

>

> Cheers

>

> Tim

Re: Motobecane 50 engine installation

By bracket do you mean the limiting hook? It grabs the spring to limit the engines movement.

Re: Motobecane 50 engine installation

Just a thing about that bonding strap - shytiest place is on the long bolt - I replace that with a new strap going from a intake stud to the lower external coil mount stud, basically more direct to where the electrical bonding is needed.

ALSO two ways to tight up the long bolt correctly so the new silentbloc mounts do not self destruct early from radial shear:

Method 1: snug up the nut so that the engine can swivel without resistance but tight enough so there is no side play.

Method 2: tight the bolt up right tight with the engine swung bac at the position of full variaton.

Re: Motobecane 50 engine installation

Pushrod Fifty /

I take pictures when I start tearing things down, I may not get back to the project for some time. Mobys have so many tiny parts its easy to mix it up.

20200710_151039.jpg
« Go to Topics — end of thread

Want to post in this forum? We'd love to have you join the discussion, but first:

Login or Create Account