mounting the enine to the frame

[700 efi guy]

so I'm wondering what people are using between their engine and frame. I want to put a piece of rubber in there to take up a bit of the vibration. I don't want to go too thick though for obvious reasons. My other question is hard to explain. I'm making a bracket that the engine will mount on. the bracket will then mount to the frame with 4 bolts. there is a 5th bolt welded to the front of the bracket. the bolt will go through a piece on the frame and have a nut to tighten or loosen the chain. how much adjustment should I allow for the chain. (I'll be cutting grooves into the frame where the braket mounts to the frame to allow tightening) should I put a spring between the nut and frame to protect against over tightening? will spring washers be enough to keep everything from shaking loose?

 

[modelengineer]

I wouldn't put anything between the engine and frame. Just bolt it straight up. Almost all motorbike engines are solid mounted in the bikes. I haven't noticed any vibration in my kart with a solid mounted engine, and mine is supposed to be quite an unbalanced engine being a twin cylinder 180 degree crank.

 

[DirtTrackRacer_07]

I would just mount the motor clean to the plate.

Just tighten the mounting bolts tight and use locking nuts or lock washers to keep everything together.

I would change the single adjustment bolt in the center to a two adjusting bolts, one on each side of the plate because you want equal amount of adjustment on each side to make sure everything stays straight.

I mite of confused you but i hope understand what im saying.

Do you have any pictures of your set up?

 

[700 efi guy]

nope not confused at all, I already welded the bolt there too, I guess I could cut it up...

do you think 1 inch will be enough adjustment? how much do these chains stretch, its either a 40 or 41. I'll try and get a pic up but it's not really welded up yet, I'll have to maybe draw in some arrows or something

 

[Russ2251]

Chain does not stretch.

 

[700 efi guy]

here's what i'm thinking

 

[DirtTrackRacer_07]

That middle pull bolt will be fine because its just a small area.

That will work as long as you have the bottom of you stationary plate braced too.

If you dont brace it, it might bend or eventually bust.

You have a good idea on where to cut and all.

Use grade 8 bolts on everything so nothing will break.

I dont see no problem with it, i thought about telling you to tie the two plates together but i think it will be better if the they float.
The sliding bolts will hold them down pretty good.

One inch of adjustment should be plenty enough movement.

What is this goin to be for? A kart or buggy?

 

[700 efi guy]

my trike, there's a couple pictures in the bike section, once I have the frame finished I'll put up some more pics

 

[DustinWolfe]

Chain does not stretch.

actually chain stretch is pretty common on 4 wheelers and dirtbikes but i think not so much on gokarts

 

[Walter Keller]

Chains

They all (chains) strech/wear ending up longer.

 

[slideways]

Looks good to me. Why not just make a solid plate though? And if you are already slotting the frame... why the adjuster screw? Just snugly tension the motor and tighten down the 4 bolts. The adjuster is just insurance at that point.

 

[700 efi guy]

well origonally I was going to go with a band brake on the clutch and wanted it tight. I picked up a pocket bike cheap that'd I've been robbing. I figure both the rotors on the rear axle should be just as good as a band brake and I'm not depending on the chain that way. I am making 2 pieces because I have angle iron in the garage, I don't happen to have any plate. I don't know why I put the adjustment screw in, it just seemed like the right thing to do.