BMW K100 High Ratio Gear Sets

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touchwoodsden
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BMW K100 High Ratio Gear Sets

Post by touchwoodsden » Wed Feb 24, 2016 4:37 pm

I don’t know what the situation is with the high ratio gear sets for K100 gearbox and final drives although I do know that Hubert Teller has been on the case but feedback has been thin on the ground. I understand there has been some problem with quality. I don’t want to get to the summer and have my P&J ready to go but sitting silently for the want of 4 gears.

It is my understanding that this has been going on now for about six months or even more, so I thought I’d better make some enquiries to see whether there is something I could do myself over here. I am also going to send Hubert the link to the company below.

I rang the automotive experts, Quaife who wouldn’t be interested in doing less than 20 sets. I guess if you are not McLaren or Ford, they are no longer interested. What I was surprised about is that they do not have the facility to actually machine the crown wheel and pinion! I think that enquiry is dead.

I rang my local “Precision Engineers” (as a starting point), who don’t do gear cutting, and they gave me the details of TK Engineering in Nottingham.

http://tkengineeringandgearcutting.com/ ... /Itemid,3/

I spoke to a very helpful gentleman, Conrad, who would be really interested in getting involved with this and he confirmed that what we are looking for with these gear sets is exactly up his street. They have done lots of gears for cars and motorcycles in the past. In particular, they do a lot of one-offs for classic machines. He would love to get involved.

I gave him the URL of this forum and he’s going to have a little look tonight.

Getting a standard set of gears to look at and supply as samples is not going to be a problem because it’s easy enough to rip a gearbox and final drive apart but obviously, they would then need measuring.

However the bit which is outside my knowledge is the bit about gear ratios. Obviously, the gears have to still fit inside the casings.

Whilst the company can measure the gears and could produce like-for-like, we would need to tell them how much room there is and what number of gears/ratios are on each.

I guess, to an extent, we are, at best, going to be stuck with a compromise of ratios and it’s not going to be able to find tune them.

In my very simplistic head, the BMW originally revved to about 8000 red line.

The Smart Diesel revs to about 3800. So, we need (I need) to double the output. I don’t know what the red line on the Daihatsu Charade motor is.

Does anyone have any idea on dimensions or numbers of teeth or ratios to do, with the BMW K 100 gearbox and final drive, what we are looking for?

Regards
Volvo V70 tank.
BRA CX 3
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1 x 125 4 stroke MZ
2 x 301 MZ
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Lombardini engined Triumph Tiger 900 (to go!)

Bert in Weesp
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Re: BMW K100 High Ratio Gear Sets

Post by Bert in Weesp » Fri Feb 26, 2016 1:29 am

Charade 1.0 has it's red line at 5000 rpm, turbo starts to be effective around 1800+.

Bert.

BertTrack
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Re: BMW K100 High Ratio Gear Sets

Post by BertTrack » Fri Feb 26, 2016 5:23 am

Scroll down on this page:

http://bmwmotorcycletech.info/ringgears.htm

Should give you some details.

Also i have found this one usefull to match fitting sets.

http://www.largiader.com/articles/gearing/

I have a 2.54 set laying about, i could measure it if you want? It came out of the bmw cruiser rear end.
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touchwoodsden
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Re: BMW K100 High Ratio Gear Sets

Post by touchwoodsden » Sat Feb 27, 2016 11:09 pm

BertTrack wrote:Scroll down on this page:

http://bmwmotorcycletech.info/ringgears.htm

Should give you some details.

Also i have found this one usefull to match fitting sets.

http://www.largiader.com/articles/gearing/

I have a 2.54 set laying about, i could measure it if you want? It came out of the bmw cruiser rear end.
Will the 2.54 gears fit. The chart seems to say that K100 are type 2 pinion and Cruiser is type 3
Volvo V70 tank.
BRA CX 3
2 CV Dolly
2 x 250 MZs
1 x 125 4 stroke MZ
2 x 301 MZ
1 x Honda C90 Cub

Lombardini engined Triumph Tiger 900 (to go!)

touchwoodsden
I luv the smell of Diesel...
Posts: 219
Joined: Sat Oct 24, 2015 2:20 pm
Location: North Wales, UK

Re: BMW K100 High Ratio Gear Sets

Post by touchwoodsden » Sun Feb 28, 2016 10:08 am

I've had a reply back from Germany which looks like being really good news:

the angle drive is alredy in december in good quality finished and
had been tested with success.
I`m just waiting on a single gear for the gear box. They will be ready
in about 3 weeks.
After that I want to install it and test it.
Then I can send the full gear set.

Best regards



I don't know much about these gears and I suspect that when the gearbox gears are changed, it's necessary to remove one of the gears on the main shaft which is then replaced with a spacer and the gearbox becomes 4 speed albeit much higher ratios. I think this is how the chap in Lithuania did it but, I don't know where he got his gears from. Does anyone know any more than this?
Volvo V70 tank.
BRA CX 3
2 CV Dolly
2 x 250 MZs
1 x 125 4 stroke MZ
2 x 301 MZ
1 x Honda C90 Cub

Lombardini engined Triumph Tiger 900 (to go!)

BertTrack
I luv the smell of Diesel...
Posts: 327
Joined: Tue Jun 05, 2012 3:53 am
Location: Netherlands

Re: BMW K100 High Ratio Gear Sets

Post by BertTrack » Mon Feb 29, 2016 6:20 am

touchwoodsden wrote:Will the 2.54 gears fit. The chart seems to say that K100 are type 2 pinion and Cruiser is type 3
I'll ask the guys that are doing mine when i go pick it up.
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touchwoodsden
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Posts: 219
Joined: Sat Oct 24, 2015 2:20 pm
Location: North Wales, UK

Re: BMW K100 High Ratio Gear Sets

Post by touchwoodsden » Mon Feb 29, 2016 5:48 pm

BertTrack wrote:
touchwoodsden wrote:Will the 2.54 gears fit. The chart seems to say that K100 are type 2 pinion and Cruiser is type 3
I'll ask the guys that are doing mine when i go pick it up.
Cheers.
I am not certain that the German gears from Hubert will be high enough ratio for the Smart motor so might end up getting more made myself. We shall see.
Volvo V70 tank.
BRA CX 3
2 CV Dolly
2 x 250 MZs
1 x 125 4 stroke MZ
2 x 301 MZ
1 x Honda C90 Cub

Lombardini engined Triumph Tiger 900 (to go!)

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