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51Back to top Go down    Re: F D ratios on Fri Nov 07, 2014 8:26 am

werewasi


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14/5 is 2.8 !!!!!!

Think you meant to say' it will be interesting.......... in 83' - because I now know what's in the 86 (the 14 to 4.9 turns hub)
Because the 83 appears to have been fooled around with, I will most probably find that its got a 20 spline shaft rather than its original 16. In fact, if its a 75 FD, it MUST be 20.

86 didnt have a 16 spline - it changed over to 20 that year and Rick said in post 32 that ALL 75s had a 20 spline.

    

52Back to top Go down    Re: F D ratios on Fri Nov 07, 2014 10:11 am

92KK 84WW Olaf

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@werewasi wrote:
@92KK 84WW Olaf wrote:
That's how the QE2, drawing 32, feet hit rocks at 40 feet.....someone forgot....

re the QE2 and the 'squat' factor'. Wouldn't the water pressure at 32' tend to compress the hull and therefore LESSEN the draught by 2.6 inches.

That was the theory and you are correct. But in shallow water its very different. Think of the ground effect when landing a plane.

What happens is that at SPEED the displacement hull displaces the water at the bow. But, further along the hull water a partial vacuum effect is created like when you pass a fast moving bus or truck. In deep water its dispelled by water from below. In shallow water the hull is instead sucked downwards. Faster speed more suckage!


__________________________________________________
1992 K100LT 0193214 101,000 miles
1984 K100RT 0022575 Baja Red bought 36,000 now 89,150 miles
1997 K1100LT 58,645 now 60,500miles
    

53Back to top Go down    Re: F D ratios on Fri Nov 07, 2014 5:49 pm

K75cster

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Wearwasi I gotta stay away from multitasking, apologies, the speedo is fine and the F/D sender sends to it. As you said 2.8 turns seems to line up with the rt f/d as suspected now, so that leaves you with a high reading tacho and no 75 f/d, maybe the boys can say whether the karamba tools also check the tacho, that may be all that is needed. Last night was good, if not alittle off centre, chatting about a German bike, drinking Jameson Irish Whiskey, Watching British speedway on the vcr, Listening to the blues night in the shed, Louisiana Bayou slide guitar, no wonder a bloke makes the odd mistake Oh and operating a calculator, busy busy busy we multicultural types.


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Keith - 1987 K75c with r100rt replica fairing and half of a 1984 K100rt

The Clever are adept at extricating themselves from situations that the wise would have avoided from the outset - QUOTE from david Hillel in Out of the Earth.
    

54Back to top Go down    Re: F D ratios on Sat Nov 08, 2014 2:27 am

werewasi

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Pulled the FD off the 83 mystery machine.

It has a 16 spline shaft as per originally fitted to the early bikes (pre 86).

so (jump in here Rick if I'm wrong) it can't have a K75 FD because they were all 20 spline.

Turned the input shaft 30 times. The hub turned 10.4 times. 30/10.4 is 2.88 so it's probably 2.81 because of the crude measurement method.

So why is it showing on the tacho that its doing 4400rpm @ 100kph. It even feels like it is revving this hard.

Maybe the tacho is wrong. How can i check it.


__________________________________________________
K100RS 1983 and 1986 (bought a 2nd and put them both together in a dark garage thinking that i would get a heap of parts from the progeny but nothing happened- think they're gay) Laughing Laughing Laughing

1985 K75, Guzzi V7 Special, 1986 GB500, 1974 T500, 1986 MB5 with the whoppa 100cc engine transplant, NC 700 SA Honda, two 1986 Kawasaki BR250s
    

55Back to top Go down    Re: F D ratios on Sat Nov 08, 2014 3:07 am

Holister

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@werewasi wrote:Pulled the FD off the 83 mystery machine.

It has a 16 spline shaft as per originally fitted to the early bikes (pre 86).

so (jump in here Rick if I'm wrong) it can't have a K75 FD because they were all 20 spline.

Turned the input shaft 30 times. The hub turned 10.4 times. 30/10.4 is 2.88 so it's probably 2.81 because of the crude measurement method.

So why is it showing on the tacho that its doing 4400rpm @ 100kph. It even feels like it is revving this hard.

Maybe the tacho is wrong. How can i check it.
Years ago I used to use a timing light and a little ignition analyser to determine rpm. Something like this. Don't know if it would work on the K's system but I think you can buy stuff like this at the local auto shop. There are really cheap units on ebay.


I was going to try to put together a spreadsheet to calc differentials from engine to rear wheel/road speed. My search for gearbox ratios lead me to this. I've not had a good look at it but it may be helpful.
www.largiader.com/articles/gearing/


__________________________________________________
1988 K100RT VIN No. 0094680
1989 K100RT VIN No. 0097367 (naked)
1996 K1100RS VIN No. 0451808
Fuel: 95 Octane
Engine Oil:Nulon Full Synthetic 15W50
Gear Box Oil: Nulon Synthetic 75W90
    

56Back to top Go down    Re: F D ratios on Sat Nov 08, 2014 4:28 am

Holister

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I've put together an Excel Spreadsheet to calculate your road speed for each gear at a specific rpm. I'll upload it to the forum file sharing space as soon as I work out how to do that but in the meantime you can download from HERE.

The wheel circumference is calculated from the radius of the rear wheel WHEN LOADED to account for different tyre heights and the tyre squashing etc. I've added the dia of the removable rear wheel cap (L/H side) into the calculations to make it easier to get a measurement. The measurement you'll need is from the ground to the bottom of the cap. If you're unsure, I'll post a pic. The cap measures 118mm. If anyone has a different size ?? let me know and I'll add that into the variables.

There are locked cells in the sheet to protect formulas but if you know what you're doing you can unlock and change.

If anyone wants to check my formulas or can see anything wrong in the way I've done this, let me know but it looks fairly accurate.

Cheers

EDIT: file can be downloaded now from the members download page. You'll need to log-in and click 'Access the member shared documents'. follow Bert's instructions.



Last edited by Kaptain Holister on Sat Nov 08, 2014 8:04 am; edited 1 time in total


__________________________________________________
1988 K100RT VIN No. 0094680
1989 K100RT VIN No. 0097367 (naked)
1996 K1100RS VIN No. 0451808
Fuel: 95 Octane
Engine Oil:Nulon Full Synthetic 15W50
Gear Box Oil: Nulon Synthetic 75W90
    

57Back to top Go down    Re: F D ratios on Sat Nov 08, 2014 5:04 am

charlie99

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just a thought

has any one considered a couple of things

this is an early version ...yes ? I have noticed that many early versions have a little and interesting fluctuations of the tacho (read over reading and slow to respond ) that later models don't .

could there be a little clutch slip evident ....not noticeable to a new to me bike owner

could both these factors contribute to the slightly over rev reading for speed ?


just ducking under cover before someone throws some spanners et al at me ,,,,but makes sense to me ....and yes I know you all think im mad goes with the territory ,,,,, affraid


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cheezy grin whilst riding, kinda bloke ....oh the joy !!!! ...... ( brick aviator )

'86 K100 RT..#0090401 ..."Gerty" ( Gertrude Von Clickandshift ) --------O%O
    

58Back to top Go down    Re: F D ratios on Sat Nov 08, 2014 5:38 am

RicK G

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Probably the needle return spring is a bit weak from age. Don't read too much into it.
Might have been like it since new and you are the first person to notice.


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If everything seems under control then you aint goin fast enough:- Mario Andretti
Bikes 1986 K100RT, 1993 K1100 LT, 1994 K1100 LT, 1993 K75 RT, 1996 K75RT, 1986 K75 GS, 1979 Z1300 Kawasaki X 2 & 1976 SR 500 Yamaha for now
    

59Back to top Go down    Re: F D ratios on Sat Nov 08, 2014 5:48 pm

werewasi

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Tks for that KH.

Clutch slippage? no sign of the slightest bit of it.

The tacho seems really good. Needle never wavers. and responds instantly.

I'm going to stop off a the 'bike' auto electrician i know and see if he can measure the revs.

Question. If the 86 has a 32/11 as opposed to the 32/12 that is expected to be in this RS. and therefore has an
11 tooth pinion, how can a different sized pinion use the same sized 'crown' wheel. The pinion teeth are at different intervals so how can they mesh with the same (32) 'crown' wheels teeth?

The text size in this messge box is very small.
How can you bump it up before starting typing.

And.
I shifted over the back disc because the 83 one was at min thickness. Replacement one 4mm.

Put new EBC pads in (but i don't know how hard they are) . Bled and feels good and firm, but the braking effect is terrible. Not much there.

Any ideas Will it come right after I've gone down a big hill and just given them a long hard application.


__________________________________________________
K100RS 1983 and 1986 (bought a 2nd and put them both together in a dark garage thinking that i would get a heap of parts from the progeny but nothing happened- think they're gay) Laughing Laughing Laughing

1985 K75, Guzzi V7 Special, 1986 GB500, 1974 T500, 1986 MB5 with the whoppa 100cc engine transplant, NC 700 SA Honda, two 1986 Kawasaki BR250s
    

60Back to top Go down    Re: F D ratios on Sat Nov 08, 2014 7:26 pm

Holister

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@werewasi wrote:Tks for that KH.

Clutch slippage? no sign of the slightest bit of it.

The tacho seems really good. Needle never wavers. and responds instantly.

I'm going to stop off a the 'bike' auto electrician i know and see if he can measure the revs.

Question. If the 86 has a 32/11 as opposed to the 32/12 that is expected to be in this RS. and therefore has an
11 tooth pinion, how can a different sized pinion use the same sized 'crown' wheel. The pinion teeth are at different intervals so how can they mesh with the same (32) 'crown' wheels teeth?

The text size in this messge box is very small.
How can you bump it up before starting typing.

And.
I shifted over the back disc because the 83 one was at min thickness. Replacement one 4mm.

Put new EBC pads in (but i don't know how hard they are) . Bled and feels good and firm, but the braking effect is terrible. Not much there.

Any ideas Will it come right after I've gone down a big hill and just given them a long hard application.
Re text size: looks to be the right size when displayed. you may need to change your screen resolution in the Control Panel or try the zoom function on your browser in the 'View' menu. There's a text size tool button on the message tool bar... but that just means it will be really big when displayed on other's computers.

Re Brakes: Some possible solutions.
- Are they the correct ones. After '88 I think?? they changed. Not sure how they differ.
- Did you degrease the disc when installing.
- New pads need breaking in. Do a few hard stops from speed.

Cheers


__________________________________________________
1988 K100RT VIN No. 0094680
1989 K100RT VIN No. 0097367 (naked)
1996 K1100RS VIN No. 0451808
Fuel: 95 Octane
Engine Oil:Nulon Full Synthetic 15W50
Gear Box Oil: Nulon Synthetic 75W90
    

61Back to top Go down    Re: F D ratios on Sat Nov 08, 2014 7:52 pm

RicK G

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@werewasi wrote:Question. If the 86 has a 32/11 as opposed to the 32/12 that is expected to be in this RS. and therefore has an
11 tooth pinion, how can a different sized pinion use the same sized 'crown' wheel. The pinion teeth are at different intervals so how can they mesh with the same (32) 'crown' wheels teeth?
The 32 tooth crown gears are made to suit and that is why you buy a gear "set" not just individual gears.


__________________________________________________
If everything seems under control then you aint goin fast enough:- Mario Andretti
Bikes 1986 K100RT, 1993 K1100 LT, 1994 K1100 LT, 1993 K75 RT, 1996 K75RT, 1986 K75 GS, 1979 Z1300 Kawasaki X 2 & 1976 SR 500 Yamaha for now
    

62Back to top Go down    Re: F D ratios on Wed Nov 12, 2014 8:46 am

jimmy62alan

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I've found this posting totally helpful and for the my diesel K100 it will be very valuable for the gearing setup. I will go for the 20 spline and this will help for the long distance trips planned.
Don't you just love this forum
ALAN

    

63Back to top Go down    Re: F D ratios on Thu Nov 13, 2014 10:01 am

AJ.Valente

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Warewisi wrote "Put new EBC pads in (but i don't know how hard they are) . Bled and feels good and firm, but the braking effect is terrible. Not much there. Any ideas Will it come right after I've gone down a big hill and just given them a long hard application."

No, that's the way they are. Strong rear brakes cause instability, so they are a bit weak by design. Generally don't use much force on them unless you have a pillion passenger. Otherwise, they are great for use around the parking lot.


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'98 K1200RS Marrakesh Red

My old K100 RT Pics and Mods
    

64Back to top Go down    Re: F D ratios on Thu Nov 13, 2014 10:30 am

92KK 84WW Olaf

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If you are doing a tight low speed turn inside a parking lot or a tight roundabout throttle plus a little rear brake to drag the rear helps you around it in a very smooth curve, helps the K to drop in without falling in.

But you don't want too much rear braking. Fact is that you can get so much weight on the front you can skid the rear easily if its over braked. But the front will take a lot of braking because its glued down. Unless you have an old hard front tyre in which case disaster can await.


__________________________________________________
1992 K100LT 0193214 101,000 miles
1984 K100RT 0022575 Baja Red bought 36,000 now 89,150 miles
1997 K1100LT 58,645 now 60,500miles
    

65Back to top Go down    Re: F D ratios on Thu Nov 13, 2014 4:04 pm

Dai

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I have an utter dislike of the standard rear brake setup. I suppose BMW put that terrible rubber block between the pedal and the master cylinder with the intention of making it difficult to lock up the rear wheel BUT! for me, in practice it was just the opposite. The complete lack of feel from the brake pedal encourages you to press harder until SQUEEEEEEEE Surprised-o: After that happened twice I introduced the rubber block and its associated metal disc to the crap in the bottom of my workshop bin (trashcan) and replaced it with a solid stainless steel rod. The result is much more feedback from the pedal and far less tendency to lock the rear wheel. It wasn't just me either. Two friends who are also brick riders prefer my setup to the standard one.


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'83 K100 upgraded to K100RS spec
Others...
'78 Moto Guzzi 850-T3, '79 Moto Guzzi 850-T3 California,'93 Moto Guzzi 1100ie California,
'03 Suzuki Blandit GSF600SK3 (NFS any more because wifey has claimed it)
    

66Back to top Go down    Re: F D ratios on Thu Nov 13, 2014 4:11 pm

sidecar paul

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Dai,
I found that a solid rod didn't give any feel at all. scratchSo I made a 3mm thick washer to fit over the rubber which reduces the squidge to an acceptable level.

Each to their own.

Paul.


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'84 K100RS (0014643) (owned since '85), 86 K100RS (0018891) with Martello sidecar (built as an outfit in '88),
'51 Vincent (since '67),'72 Montesa Cota (from new), '87 Honda RS125R NF4 (bought 2015)
....No CARS never ever!
    

67Back to top Go down    Re: F D ratios on Thu Nov 13, 2014 9:36 pm

Dai

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I rather suspect that 'feel' is a direct ratio of foot pressure to perceived deceleration. As you say Paul, everyone will have their own opinion on what constitutes good 'feel'.


__________________________________________________
'83 K100 upgraded to K100RS spec
Others...
'78 Moto Guzzi 850-T3, '79 Moto Guzzi 850-T3 California,'93 Moto Guzzi 1100ie California,
'03 Suzuki Blandit GSF600SK3 (NFS any more because wifey has claimed it)
    

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