Looking for engine dimensions

[Alienation420]

I have a custom project and really want to run an xs650 motor. I'm trying to see if the motor will fit without frame modification, but can't find anywhere that has dimensions for the motor itself. I'm looking for how long the motor/final drive assembly is, as well as from the bottom of the case to the top of the head, width and length of the top end of the motor etc. Can anyone help me out?

 

[Jim]

Just eyeballin' a tape measure, so roughly.....

"how long the motor/final drive assembly is" 14 1/2".
"bottom of the case to the top of the head" 21 1/2".
"width and length of the top end" 12" W. 10" L.
Crankcase width is about 16"

 

[Alienation420]

Would it be possible to get a profile shot of the motor with the measurements superimposed? Just looking at my frame and can't quite view it... If not, that's alright. Just REALLY hoping I can make the motor fit

 

[Alienation420]

Never mind! Just eyeballed my frame and not a chance it will fit without modification. Thanks for the super quick reply!

 

[Jim]

What frame are you using?

 

[Alienation420]

Cleveland cyclewerks hardtail frame. Was just a bike I've had laying around and been wanting to put a different motor in it for a while. I have like 15.5" from the front of the cradle to the seat tube, and about 19.5" at the front from the bottom of the frame to the gusset. Maybe a 400 motor? Needs to be left side chain drive. Don't really want to cut the frame, but if I have to..

 

[Jim]

It'd be close. Got some pics of the frame?
Oh.... and welcome to the forum!!

 

[Alienation420]

Here is kind of a side profile. Right now it's a measly 250 motor, but with my trip coming up in June, I need more power, as I'm building this for the Born Free event.

 

[Jim]

Well, if you're willing to do a little frame modding, I'd guess you could make it fit. It's pretty close. Would make for a nice bike.

 

[Alienation420]

I just thought of the xs400 motor as well. With the smaller displacement, I'm guessing the motor would be a little shorter? I just know I need a parallel twin.

I'm just wondering how the 650 motor sits and where the measurements are. Like the top of the head at the back end of the cylinder, and how tall that is in comparison to the front. If that makes any sense?

 

[Jim]

I did a weight and balance on my motor last yr. These are hard horizontal dimensions. In this pic it's tilted forward about 5 deg more than it would be mounted in the frame. Maybe you could figure some dimensions out from it. I'd help more right now but Chiefs are taking the field soon.

 

[Alienation420]

Awesome, thank you! By those calculations, the bottom part of the case is only 12.5" roughly, which works perfect, it's just the height of the heads! Wondering how much shorter the 400 is vs the 650 (to the top of the head wise)

 

[Jim]

I'll get you some numbers after the game.

 

[Alienation420]

Thanks, much appreciated! Trying to avoid cutting the frame if I have to.

 

[gggGary]

I did a weight and balance on my motor last yr. Chiefs are taking the field soon.
View attachment 158485

I'd never guess you had an aviation background.........
Go Chiefs!

 

[Jim]

How 'bout dem Chiefs!! Ahem.... sorry.
Here's the frame engine mount dimensions...

Aft mount.

Fwd mount.

Upper mount

Overall.

 

[Alienation420]

Perfect! You are a life saver, sir. Now I know exactly what I have to work with/towards. Thank you a million!

 

[Jim]

 

[lakeview]

The picture of your bike as is looks nearly perfect. Will the frame support the additional output of the 650 motor (40 - 45 hp?)

 

[Alienation420]

Thanks Lakeview. But I just need some more power out of it for an upcoming trip. The frame will handle alot more power that comes with a bigger motor, but I plan on adding a few gussets here and there for added strength just in case.