. I hope you
all understand that.
Well, maths is a great lesson. Especially when your are bored and finished all your work, because it seems that that is where all my creative ideas
come from. Anyway, I dont want to, and probably never will force myself to buy a diff for mid mounted bike engines for several thousands of dolllars,
so i whipped something up. It is basically exacly the same as a conventional Bike engined car. Except with out a propshaft. In short, a bike engine
mounted longitudial with a universal joint is attachet to the sprocket, then joins directly to a conventional car diff. I feel proud . I hope you
all understand that.
Make a picture you are sure we all understand!
When i have more time i will do a much more detailed image
Rescued attachment untitled2.JPG
does the engine essentially touch the diff with no propshaft, just the UJ?
I don't want to rain on your parade, but I'm 99.999% certain it's been done already.....
However, and this is the main thing, it is still a doable and workable solution...
So I'd research a bit more then go for it...
In fact isn't it what 99% of bike engined cars do now - except the diff is a lot longer....
on the positive it means lots of readily built bits (tiger in the uk do quite cheep prop shaft converters for bec's i believe).
The downside is that the engine has to be offset to the nearside (left when looking forward for all those not in the uk) so the prop shaft lines up
with the output from the bike's gearbox.
The idea I'm researching hopefully gets round that (although is a little more expensive). Get a Porsche 928, 944 or 968 gearbox. Its a transaxle,
feed the bec's / other engines input into that via a prop (torque tube) and away you go.
Another solution would be to use a Mini diferential and modify it to accept a sprocket. Then use engine in normal east-west configeration and a chain
transfering drive to diff.
It has been done many times before. Is very compact and light. Plus the axle movement is not transfered to engine. 
Terry
ps. another benefit is easy gearing changes for different circuits.
[Edited on 20/11/03 by Spyderman]
Another minor point.
What is needed to couple the units is actually a compliant drive coupling (readily available) rather than a plain U/J
A U/J allows for angular misalignment and movement while holding two elements on a perfect center line.
A compliant coupling on the other hand allows for a little angular misalignment and a little eccentricity between the two elements....very common
between say a pump and a motor....
Small point, but worth mentioning....
I posted this idea a while back as a cheap alternative for the MK GT1 to using the quaife torque biasing thingy. I'm sure someone else thought of
it before me!
for bike mid engined I'd drop an engine in inline with a slippy sierra axle.
Ned.
It's been done. The Coram LMP uses it to great effect (it was thought of about 7 years ago). And I think it may be copyrighted...
Wanna photie? I'll see what can be arranged. Have a peek in tadltd's pic page in the next few days.
Shug. 
look at http://www.spiritowners.f9.co.uk/maximus/maximus.htm
its my mates project, my idea to use the sierra diff to drive the front wheels
150bhp v4 bike engine and it is v.v.v.v light!
Col,
there don't appear to be enough wheels! and it'll be a bitch for wheelspin!
very interesting stuff.....
Ned.
all i can say col, is well done to your friend for getting it so far, but he really needs to come off the hallucinogenic substances! a mad and unique
idea. single seater? will weigh two thirds of bugger all...
whats he aiming for, 350kgs?
i have an idea- stick the engine to a rotatable turret, (probably atatched to the steering wheel with shoe laces or something to control) then put a
propeller on the sprocket of the engine. come to think of it, you could use the down draft to power a cushion of air for the car to sit on and reduce
friction. you could even go on water with it!!
Russ.
We have them here already...called airboats..
if you are interested...
http://www.airboattrader.com/boats_under_$5,000.htm
[Edited on 20/11/03 by Alan B]
quote:
Originally posted by Spyderman
Another solution would be to use a Mini diferential and modify it to accept a sprocket. Then use engine in normal east-west configeration and a chain transfering drive to diff.
!!! Jeez! And why is the steering wheel upside down? fuckin bonkers you aint wrong, D-day will be tuesday-wednesday, he is having the exhaust made and fitted on tuesday, he will be able to run it up
propperly. I will try to borrow a vid cam to capture the moment and post it on here, should sound orgasmic! 1200 cc of v4 with V-boost on a manual
switch!
It weighed in at about 300kg before with a 1.4 renault 5 cast iron lump in it so it should weigh in at less now, also with alloys rather than lumpy
old renault wheels.
its not the best looking thing you have seen but it will go like poo off a stick! will keep you posted.
he has bought the rights to the Hudson kit car company and will be producing these kits soon. The kit is not SVA compliant but other owners have made
them conform with a little work.
The guy who manages the website has made a 4 wheeler version and after seeing the max installation is going to go down the same route now. The kits
will be available ready to install a max engine - brake upgrades can be made with Renault 5 gt hubs and callipers or by having clio uprights and hubs
machined to fit.
Ned :wheelspin will be a problem and i think it will understeer like a bitch i bet? powering out of a corner could be interesting, especially in the
rain!
Sgraber : the steering wheel is on upside down so he can see the all important speedo when the dash is fitted.
[Edited on 20/11/03 by colmaccoll]
[Edited on 20/11/03 by colmaccoll]
Just checking - is the diff installed the right way up? (i.e. shouldn't it be up-side-down to drive the front wheels - it probably is, but I
can't tell as I have no experience of Sierra diff's! )
He may also want to look at the position of his steering rack and/or the out-board track-rod ends before driving it...
Can I suggest connecting the rear wheel to a set of bicycle pedals for reverse?!
Can't wait to see it go!
Steve.
could someone post details on how you modify the mini diff and have a guess as to how much power it can handle before it goes pop.
quote:
Originally posted by Alan B
Another minor point.
What is needed to couple the units is actually a compliant drive coupling (readily available) rather than a plain U/J
A U/J allows for angular misalignment and movement while holding two elements on a perfect center line.
A compliant coupling on the other hand allows for a little angular misalignment and a little eccentricity between the two elements....very common between say a pump and a motor....
Small point, but worth mentioning....
tadltd: the diff is the correct way up as the max engine spins the other way compared to blade/zx9 etc, hence you couldnt use a max engine in a rwd
locost mores the pitty 
, plenty bhp and more torque than you can poke a stick at!
This is q quick thread.... 20 replies in just over a day
....(make that 21 )
and still no one has answered with a "how to modify the mini diff to make it chain driven" just how many more posts are we going to
get???
quote:
Originally posted by colmaccoll
tadltd: the diff is the correct way up as the max engine spins the other way compared to blade/zx9 etc, hence you couldnt use a max engine in a rwd locost mores the pitty
quote:
Originally posted by MikeR
and still no one has answered with a "how to modify the mini diff to make it chain driven" just how many more posts are we going to get???
quote:
Originally posted by Alan B
quote:
Originally posted by colmaccoll
tadltd: the diff is the correct way up as the max engine spins the other way compared to blade/zx9 etc, hence you couldnt use a max engine in a rwd locost mores the pitty
Ah so the diff is actually running in reverse all the time...I'll be interested to see how it holds up
quote:
Originally posted by Spyderman
......... Hopefully with such light loading it will endure ok. Also as there are so many in the scrap yards I don't suppose it is too crucial!
Some of you may not know that I actually had a VMax/Venture engine in my garage to be installed mid-engine into my car in place of the 4AGE, but I
just couldn't convince myself to use a reverse running differential... Just picture how the gears in a differential mesh together. Then think
about the loading on the gears in reverse. Not pretty. I simply can't imagine it would last very long So I scrapped the idea.
However --- I truly want that unbelievable trike to succeed! and I would LOVE to hear updates on the FWD VMAX project as it makes it onto the road!
Specifically related to how scary it is and how the diff holds up!
Graber
Rescued attachment 4AGEvsVMAX.jpg
quote:
Originally posted by sgraber
However --- I truly want that unbelievable trike to succeed! and I would LOVE to hear updates on the FWD VMAX project as it makes it onto the road!
Graber
The diff is running the right way! it will power the car forwards as it is at the front and the max engine spins the other way.
What i was saying was that in the conventional rear diff- front engine the max spins the WRONG way but with the diff at the front it will be ok.
i will keep you all posted on its progress.
quote:
Originally posted by colmaccoll
The diff is running the right way! it will power the car forwards as it is at the front and the max engine spins the other way.
What i was saying was that in the conventional rear diff- front engine the max spins the WRONG way but with the diff at the front it will be ok.
i will keep you all posted on its progress.
Is the diff used the Front diff from a 4x4 Sierra? I have never seen that configuratoin... If so then, perfect!
No worries mate! I am now in possession of
1 x Video camera
my mate is now in possession of
1 x 3 wheeler with Installed v-max engine with complete bespoke exhaust system.
Will post results of our combined efforts as soon as i can figure out how to!
Here you go lads:
Mid Engined V-MAX Starting Up
Mid Engined V-MAX Revving
[Edited on 26/11/03 by colmaccoll]
Check out the above links,
Yeah! That's great! Love it when they fire up instantaneously like that!
Say, that sounds very business-like!
How soon before we can see some full speed runs up and down the alley way!?
Graber
Should be blowing diffs by about Monday i recon! Just waiting for brakes and trying to investigate a hydraulic clutch that wont bleed!
Seriously worried by the reverse running of the diff now
A) we will get that reversing whine and
B) i dont think it will last that long with 150bhp being forced through it the wrong way.
To replace the diff means an engine removal too , not a complete removal but it needs to sway sideways shall we say!
Still..... it sounds sweet though, that exhaust cost £750 not including the end cans which he already had
what about using the 4x4 front diff ?
its certainly worth considering,
I have never seen one and dont know which way the input shaft rotates, can anyone offer some advise? even a piccy?
Had a brain wave .....
BMW bike engines are shaft driven to the rear (well some are before someone tells me model x isn't). Now this is going to mean a little offset to
the diff but at most we're looking at the width of the rear tyre plus a little.
So back to the original idea of bike engine and car diff - except the engine doesn't have to be really offset to the left!
Try a search of this forum, as I think I described a method of doing what you're talking about a while ago. Basically, a Golf diff is the one you
want, as they come with flanges and CV joints, and there are a huge variety of stock shaft lengths to chose from. All that's required is a
fabricated/spun cover for the diff with a couple of O-rings and a bung/plug for the oil.
Here's a pic of something more expensive.
Rescued attachment ZX12_trans.jpg