and it was over, before it began!

At this stage I am only building this box for my new car and" IF " I can't break it then and if time permits I might do some later.
I am happy to show the details of construction and method if someone wants to have a go at building one.
The std bike output shaft needs a spline ground to suit the mini pinion. The shafts are as hard as hell and the only way is to grind it in a tool and cutter grinder. The input shaft is also ground with the same spline to take the center of a input gear,but a new gear[from the idler shaft] is fitted to the spline hub.
The main shaft has housings to fit the original case holes to suit the new taper rollers. This part remains unchanged in the case.

In the pics , the 25mm machined off is in the end of the case. This is from the original face down to a depth of 25mm and the new end plate is bored to take the bearings to locate the two shafts and the selector drum. I just mark out the centers of the various shafts and set up the plate on the lathe face plate and bore to suit. The original idler gear remains in the same position but is setup for taper roller bearings. The whole gear train is mounted onto the new end plate and does not require fitting into the other side of the gear train case.

The other end of the input shaft locates where the original reverse gear sits in the case The center is about 1.5-2.0mm from the original center and this is line bored from the new end plate to 58mm to take the bearing.

Reverse is the original mini gears mounted to the shafts. These are not in mesh and to get reverse direction a sliding idler gear meshes between the two shafts, or if you want 6 forward and 6 reverse gears then it can be done on the input gear train

It might be as clear as mud but I will post some pics of the end plate as soon as it is finished and is ready to weld in.

_________________
Research is the difference between speculation and investment. Anyone who copys some one else will always be second
www.minisprintgt.com

if some of us were interested in attempting something like this, would you do this part of the job which cant be done with a dremel at a fee.

i wouldnt mind fiddling with this sort of idea, but i dont have a machine shop at my disposal.

_________________
Aussie Leyland, Aussie Factory, Aussie Mini S.

As a few other people viewing this topic, i am also interested in it. Is the honda cbr1100rr or vfr800 the only gearsets that would suit this design, what about a cbr1000 or similar. Also what components are needed exactly, i see there is the main gear assembly.

Cheers
Sav

_________________
73 Clubman - Working Progress

Looking at pictures of the gear set they look the same- but would have different gear ratio's

all the cbr shafts and center distance for the 600,949,1000 and 1100 [from 2000 onwards] are all the same but there are different ratios depending on year and model.
From what I have found out the vfr 800 around 2004 and the new vfr1200 have same gear shafts as well. I have not recieved the gear set for the vfr so not 100% sure, but the supplier assures me that they are the same.

I hope to get this box finish next week and could be looking for a test car[if you are still game Craig] and see how it goes.
Once the vfr gear set turns up then I am going to build up a box with that gear set in with a few different mods after working on this one. I am setting up to cut the new gears for the drop gears instead of using std ones for the vfr box.

The gear sets are available from USA and sell for between $80 to $150 depending on model bike. The selectors and shift are usually sold seperately.
The honda stuff is cheap and readily available from USA but the tooling and machining and construction takes time, I do not have CNC machines

_________________
Research is the difference between speculation and investment. Anyone who copys some one else will always be second
www.minisprintgt.com

If this is your work in the back of the Ute David....then I am truly sorry not to have shaken your hand and introduced yourself....I was a little busy with a few VIP's but thats no excuse. Cheers, Mick

Great work young man

_________________
"Show me the Mini!"

wooooowwwww, fark

Yep, that box sure is a great piece of work.
I doffs me hat....

_________________
DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

well that ain't my gear box, but someone has done a very good job of copying my design with a VFR gear set. The 6th gear ratio is the give away.
They even copied the set-up using the mini 1st and reverse gears.

So who is the gentleman who did it.

_________________
Research is the difference between speculation and investment. Anyone who copys some one else will always be second
www.minisprintgt.com

I also stood there looking at it , the work manship that went into it
WOW !

I really like this. I'd be very keen if they were up for sale
Did I say I really like this?

i`m sorry but i just have to say here (& i mean this in the very nicest possible way)

Dog engagement gearboxes are really only any good for racing purposes

we have been using 6-speed dog boxes in our minis for quite a few (over 10) years & i just want people to understand that it`s not really a "Nice" box to use around town,,, not nice at all

now i`m sure David will chime in but i think this needed to be said ,,, anyone "thinking" they can use this type of box on the road is just kidding themselves

_________________
No offence intended here but--> anyone writing a book about minis 30 years ago may not have experienced such worn or stuffed-with components as we are finding these days.

You should put your heart & soul into everything you do.

"dog engagement" means there aren't any synchros as we know them, yeah?

so when using this gearbox your arm would really get a workout from bashing it through the gears

it does look pretty though

well I just had a closer look and I am wrong. It's not a VFR gear set 6th ratio on those is .89:1 .
It has only 1 selector shaft and the 1st gear is smaller than the 1100 RR set.
Interesting it looks like they have removed most of the drop gear end plate and welded in a 25mm ?? plate . The main shaft looks like a complete new one made and the idler gear[ not the original big one] where the input use to be is running on the main shaft extension.
The reverse is the std mini 1st gear mounted on the pinion end of the main shaft and engages by using the std 1st gear selector drum. The new input shaft has a gear with a idler running constantly and this give reverse direction when the mini 1st is selected.
I can not see where the selector shafts/linkages connect to the selector drum.
Over all pretty good job.

_________________
Research is the difference between speculation and investment. Anyone who copys some one else will always be second
www.minisprintgt.com