58 replies to this topic

[darkcat]

Tupers: Thanks! yes, me too!!!

David: yes i would rather have used a decent car LSD, however for a 1.0L block this thing is huge, and leaves very little room to play with.

Indeed the low-end and 2wd ATV's mostly have a solid rear axle, but the higher end 4wd ones and the work-horse farm machines have fully independent suspension, front, middle and rear diffs, diff lock etc etc.

I am now faced with the challenge of building a frame to support the engine and diff.

2 questions for you fabrication peoples:
1: Whats the best type of kit for finishing/prepping/profiling tube ends?? a disc sander? all the ones ive seen seem to be geared towards woodwork...?
2: I need to get the driveshafts spliced (ATV inner pot/Cv joint to the mini outer CV) - obviously not something i can tackle myself as i dont have access to lathes etc. Any ideas where i can get this done?

[Tupers]

1: Whats the best type of kit for finishing/prepping/profiling tube ends?? a disc sander? all the ones ive seen seem to be geared towards woodwork...?

The best tool would be a tube notcher. If you're only doing a few tubes then you may be better off marking the tube with pen and using a flap disc on an angle grinder to notch it.

2: I need to get the driveshafts spliced (ATV inner pot/Cv joint to the mini outer CV) - obviously not something i can tackle myself as i dont have access to lathes etc. Any ideas where i can get this done?

I think either Watsons or Allspeed offer a drive shaft shortening/modification service.

[darkcat]

Thanks - I ended up buying a disk/belt sander - as im only using square section at the moment.

Thanks for the shaft advice, i'll contact them today

progress update:
Spent the afternoon tacking the messy task of de-greasing the driveshaft/cv assemblies in prep for (whoever does the) shortening.

Next task: do a full, measured mockup of the diff and engine and take measurements for the frame/cradle. This is intended to be solidly mounted to the engine and diff, and then mounted to the subframe via poly engine mounts.

[Chris79]

Righty then!
We have progress.

Having tracked down a suitably small but rugged diff, and a pair of driveshafts, i decided i'd mock up the positioning:

The only down-side with this diff is that its straight-cut, so will probably be a bit noisy. but to be honest over the chain and engine.... well you know!



and in-situe:



Monica watching on.....





So the plan is to attach a sprocket to the end of the diff input shaft, and drive it via chain from the gearbox output
The diff is a 3.5:1 ratio, which is higher than the 2.4:1 of the original rear sprocket on the bike - therefore gearing this for acceleration as opposed to top speed... i honestly dont want or need to go over 90 in a mini!!! let alone 180!!!!!!!

Thats gotta be the quickest skateboard around...

[miniblade81]

how are you getting on any joy

[darkcat]

Im struggling with the custom driveshafts... ive had 2 quotes so far, and they wand nearly £300 EACH, which is clearly not going to happen.
Probably because im asking motorsport engineering companies, im going to have to find a local machine shop that can do splines.

I mean jesus it's a steel rod with slits in the ends!! i'd do it myself if i had a lathe...

Waiting on a couple of other quotes

[R1mini]

I personally would get them cut and welded first until the conversion/diff, etc has been proven, if everything works out then spend the money on a set of custom driveshafts.

Geoff Berrisford from GB Engineering does unbreakable driveshafts at £160 each, as long as he has your splines he could do them

Cheers
David

[darkcat]

r1mini: yes im going to do that for the one, for now, however the other (driver's side) will need to be fully custom, as the diff is so far left...

[Tupers]

Seen as you've got to have custom drive shafts have you thought about running equal lengths shafts with a supported shaft going from the diff you the right side of the subframe?

[darkcat]

Seen as you've got to have custom drive shafts have you thought about running equal lengths shafts with a supported shaft going from the diff you the right side of the subframe?

Yes - thats EXACTLY what im going to do - due to the un-avoidable diff location, its actually my only choice.

i started building up the engine support cradle yesturday, its going to be a complicated frame....!!

[darkcat]

Geoff Berrisford from GB Engineering does unbreakable driveshafts at £160 each, as long as he has your splines he could do them

Cheers
David

Just gave them a call - sounds reasonable

[darkcat]

coming along:

Added a combined strut brace and upper engine stabiliser:

[miniblade81]

wheres the clutch

[brad-the-bear]

within the "engine" am guessing

[KieranB]

Is that a TVR in the background. Keeping a close eye on this project, will be awesome when its finished

Kieran