How short is 1st?

Started by koko64, December 14, 2018, 12:52:36 PM

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koko64

I forget how short 1st gear is on an M900. My "95 Japanese delivery motor in my "94M900 has 15/41 gearing which is great on the open road but I can barely get across an intersection in 1st. It's so short it makes me want to gear it up, but then the highway acceleration is great and 60mph rpm is still cruisey at about 3900.
Did the Japanese models have a different box?

Just a note, the bike has plenty of torque and can launch in second quite easily on level ground. Nearly redlining across the end of the intersection .
2015 Scrambler 800

WTSDS

Originally I was happy with the standard 15:41 gearing on my 2000 M900 ie but then I started doing regular long ( 2000 km round journey )  highway rides and at 110 kph in 6th was looking for another gear. 15:39 fixed that nicely.

Now I live in the bush and our driveway is rocky and rutted and I have to feather the clutch in first until reaching a dirt road. Once on the bitumen the gearing is perfect, the only problem then is dodging the kangaroos, wombats, wallabies and deer ;-)
2000 Monster Dark 900 ie   Stock except for low Staintunes and a centrestand. 15:39 sprockets make for excellent highway gearing

Speeddog

AFAIK, there's 4 boxes that fit the big cases; 6-speeds of Regular, Close, and Corsa spreads, and some funky 5-speed on a few Elefants.

Regular and Close have a 2.47 low gear, almost same as the 2.50 small-case 6-speed and 2.46 small-case 5-speed.

'95 M900 carbie was the Regular box, with a 2:1 primary gearset.
'00 M900ie is the close box, with a 1.84:1 primary.
Same setup as my S4, and I liked it a lot better with a 39t rear sprocket vs the OEM 37.
Just the difference on the primary gears is ~same as a 3 tooth change on the rear sprocket, or the difference between 5th and 6th, so it's noticeable all by itself.

There are 16t front sprockets, and they will usually clear the big cases by a tiny margin.
Won't clear on the small cases.
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koko64

#3
I would love taller 1st and 2nd gears, I don't mind the rest as they are with 15/41 as it's great on the open road and canyons. The motor has plenty of torque for its capacity. I wonder what the primary ratio is for the hunting tooth Vee Two kit?
This bike is also more sensitive to lighter flywheels too (making me suspect a lightened crank as we've discussed). I can't get away with lighter flywheels like I have on other 900/944 Desmodues. It certainly spins up quite well.

CheersðŸ'
2015 Scrambler 800

GK

Quote from: WTSDS on December 17, 2018, 02:22:14 AM
Originally I was happy with the standard 15:41 gearing on my 2000 M900 ie but then I started doing regular long ( 2000 km round journey )  highway rides and at 110 kph in 6th was looking for another gear. 15:39 fixed that nicely.

Now I live in the bush and our driveway is rocky and rutted and I have to feather the clutch in first until reaching a dirt road. Once on the bitumen the gearing is perfect, the only problem then is dodging the kangaroos, wombats, wallabies and deer ;-)

On my 01 Monster I run 14/40 and do round 4000 at 100 kmph.
When I first got the bike it had a 15 front and I had to slip the clutch a lot to take off.
2001 Ducati  Monster 900S ie
JE high comp pistons, bit of porting, open airbox with DP filter, PC3 with custom map, CCW matched injectors, Termignoni cf slip ons, 14:39 gearing.

Gone but not forgotten!
Honda VFR800i, Honda CBR600F3, Honda CBX750, Norton Commando 750S, Suzuki GS750, Yamaha XT250, Kawasaki Z250, Kawasaki KX80, Honda XL250, Suzuki TC100.

koko64

#5
Your model has the close ratio gearbox and different primary ratio (1.84:1 Vs my old girls 2:1).
I must be one of the few that like the close ratio box (once geared down). I could have settled for 15/41 or 15/42 with your bike. Your bike pulls like train with its mods and revs right out [thumbsup]
2015 Scrambler 800

GK

15/42 is close to 14/40 though right?
One on the front pretty much equal to three on the rear?
2001 Ducati  Monster 900S ie
JE high comp pistons, bit of porting, open airbox with DP filter, PC3 with custom map, CCW matched injectors, Termignoni cf slip ons, 14:39 gearing.

Gone but not forgotten!
Honda VFR800i, Honda CBR600F3, Honda CBX750, Norton Commando 750S, Suzuki GS750, Yamaha XT250, Kawasaki Z250, Kawasaki KX80, Honda XL250, Suzuki TC100.

koko64

Yep. I tend to run more ride height so I gravitate towards a 15 T front sprocket.
2015 Scrambler 800

stopintime

Quote from: koko64 on December 22, 2018, 10:03:11 AM
Yep. I tend to run more ride height so I gravitate towards a 15 T front sprocket.

?
252,000 km/seventeen years - loving it

ducpainter

Quote from: stopintime on December 22, 2018, 10:14:27 AM
?
There's a larger possibility of a 14T front wearing out the chain guide and cutting the swing arm with raised ride height due to swing arm angle..
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stopintime

Quote from: ducpainter on December 22, 2018, 10:25:20 AM
There's a larger possibility of a 14T front wearing out the chain guide and cutting the swing arm with raised ride height due to swing arm angle..

Ah - that old song  [thumbsup] I have always had a slightly raised ride height + heavy linear spring. The chain guard is still just fine.
252,000 km/seventeen years - loving it

koko64

Maybe the old swingarm design may is more prone to it. I run up to 30mm more ride height (about 10mm more on the wishbone adjustment) and also run the chain on the loose side of spec to protect the swingarm and transmission bearings. I've seen the chain runners sawn through.
2015 Scrambler 800