LocostUSA.com

Locost 5.0 wrote:Thanks for the drawing, do you think there should be any type of shock absorption between the two?

Rod

No.

if you are building the parts anyways, you could always put in a Guibo, see the thread about them.

You might have a look at this. Check out the coupler at the bottom of the page.




http://www.transworks.biz/minidiff.html

Michael

I also have an old dune buggy fiberglass body waiting for its turn to be built into a street/autocross car with a custom LoCost frame and a motorcycle engine mounted right behind the seats (firewall of course). I am wondering about using a transfer case from a 4x4 as the rear diff.

Mounted inline with the engine drive sprocket with a sprocket bolted on to the (T-case) single shaft and the axles mounted to the double sided shaft. I would be able to use the stock engine clutch. I could even change gearing depending on sprocket sizes.

I obviously don't know anything about T-cases or I would know if this would work or not. I have only seen a couple in a shop in the past and it seems like it might work. Do the shafts turn the correct directions for this to work? Do they make T-cases with any type of limited slip? I notice that some are aluminum or even magnesium cases so they might be nice and light. Just an idea. I'm full of 'em. Or something like that...

Perhaps someone who actually is familiar with T-cases will speak up.

I'm guessing here, but I think they ran a chain from the bike motor to the nose of the diff. That's why the bike motor is offset. It's probably higher as well. This si a cheap way to do it.

If you use a bike engine, you have to use the gearbox as well; it shares the same casting. Well, the American v-twins don't...

--Chris

Reviving an old discussion, but here is some info for those interested in adapting a bike engine to a VW Type 1 Beetle transaxle...

http://www.youtube.com/watch?v=g5J6-V2JYJU

http://www.youtube.com/watch?v=A9N-c-uPCNc

http://www.youtube.com/watch?v=NbVyE5ZGj9k

bryan

excuse me for butting in here, i have some questions about the coupler.

1. does anyone know of a cv joint that would fit the input shaft of a vw type 1 transmission?

2. why does the coupler need the nut attaching it to the bike engine if engine and trans are rigidly mounted?

3. if you could get a sprocket large enough, and drill and tap 6 holes in it and a suitable step to locate it centrally, add a 6 holed spacer for the center nut clearence, and bolt the cv joint to it would this work, assuming you could find a cv joint that would attach to the vw input shaft spline count?

just askin'

However you decide to do it I just hope for a build loge that is as detailed as your last.

Paul

1) I do not think there is a cv with a female spline that would fit a vw input shaft. A support bearing would be required anyway if the cv is connected to a driveshaft.
2) The nut prevents the sprocket from rocking back and forth between shifts on the splines. The splined area is very small compared to a slip yoke. It will ruin the bike output shaft as well as the female splined area.
3) I don't think there is enough clearance to the case on most bikes to fit a drive sprocket large enough to drill to fit a cv bolt pattern and still have reasonable edge distance to the holes. Better off to start from scratch.

You have to get creative on the VW install... the guys that build electric VW's use the center section from a VW T1 clutch disc to
get the female splined center section. Give me some time and I'll post a couple pics of solutions, or bits & pieces for you to look at.

bryan

Just do away with the VW transaxle altogether, and copy what the bike-engined mini buggies have been doing for at least 10 years. Search for bike engined buggy on YouTube to see what I am talking about.

Tom

Do the bike-engined mini buggies have differentials?*

I know there were (and maybe still are) store-bought ATVs that were diffless, which is fine on loose ground but doesn't work well on asphalt. Unless you want to go in a straight line a la funny cars.

The differential does seem to be the bugaboo. I bought a book some years ago called How to Build Motorcycle-engined Racing Cars ("The total process of building a car is described...") and my main motive was to learn how to build a chain drive differential. The differential chapter read (if I may paraphrase), "Mail a substantial cheque for numerous pounds sterling to Quaife Engineering," and I rather lost interest after that.

*Not a rhetorical question. If there's a source for bike-engined mini buggy diffs, I'd like to hear about it.

Using a VW T1 trans as a diff is cheap & they aren't that heavy... the picture above of the Transworks box... it's a VW Rhino transmission case that has been machined down (bellhousing removed), has extra gears removed from inside (they strip it down to a reverse & 1 forward gears, & they adapt a CV style input coupling. Available - For a price.

bryan

in that case, if you didn't need reverse, could you just use a vw trans axle with nothing inside, not even the ring gear and attach a sprocket to the drive flange on one side and weld the spider gear on that side to the diff carrier, thus having the differential split the wheel speed.

the case could be shortened and the bell housing removed

will that work?

The answer is... possibly. The transmission case side plates carry the bearings that support the diff section, so it's possible. Benefit: the T1 stub axle outputs mate up to existing T1 stub axles at wheels & you maintain use of standard VW Beetle axles.

Question:
How do you lubricate the inner spinny-bits? The ring gear is usually dipping into the lube & whipping it around the inside of diff assembly - without ring gear, would there be lubrication issues?







bryan