How many gears do you need?

[Tim754]

Just read the Yamaha SC500 thread. so how many gears does a VMX big bore need ? (Yeah OK my 840cc has 5 but it also has 4 cylinders and four carbies electric start etc...) personally I am the big bore less gear change type. 4 was enough on the SC500 ,how many on the Maicos Firko? Some CCMs had three, but I have read that the gearboxes on them were a sore point. Some big bore riders your thoughts and experiences please? Cheers Tim

[Hoony]

I think 4 is plenty for a big bore 2 stoke, (my CR500 has 5, 1st is way too low and it pulls 3rd gear starts easily and i am 90kG) , so there ya go Tim that's my take.

[090]

Your right there Hoony. You never use first except for crawling through the pits maybe. I have a Vertemati big bore 4 stroke that has 3 gears, seems to be ample. Probably wouldn't work on a 2 stroke though.

[dkupf]

I think I need a 360 auto Husky so I don't have to change any :)Darcy

[brent j]

Tim I run Bonneville style gearing on my TT500's, I have to slip the clutch in first to move through the pits but I only ever use second and third for racing. Ideally I'd like to gear it high enough to use first and second as the bigger gap between the gears would give a greater speed range but it is physically impossible to get the size of sprockets I'd need to fit on the bike!

Brent

[Hoony]

its a bit off topic, but recently at a mates block i was doing some practice starts in 3rd and it was a very slight uphill on soft grass and i thought lets try 4th, i held it flat and fed the clutch ever so slightly and it pulled it no worries with a bit of wheelspin, it may be different on a very tractable dirt surface though, i don't think i would ever try it (4th gear) on race day.  i even tried 5th (top) and it bogged down a bit but then got away. big bore 2 strokes are amazing workhorses.

anyone else tried this out?

[holeshot buddy]

i think 4 gears is fine for mx i have 4 and 5 speed 500s and i prefer the 4 speed , at cd4 around broadford on the suzuki i did not go below third anywhere it was unreal do not even have to slip clutch ,clutches are for riding through pits and taking off from the gate






it ran last time i started it 

[mx250]

The 76-77 VB360 Monty has four but I believe the Montesa factory was thinking of three speed and trialed some at euro moto's but didn't offer it to the public for fear of buyer resistence (perceptions).

On big bores tuned for torque and wide power delivery 2 or 3 would get them around most mx tracks competitively. I think you'll find a number of dedicated 'factory' mx racers (eg CCM) had three speed boxes often with wider, stronger gears.  I think the 4-5 speed for production bikes was more about giving the buying public wide application for the bikes e.g trail riding  saturday, mx sunday and desert racing next week end.

[Lozza]

Fixed gear kart engines have only one doesn't hurt them at all.It matters not how many gears what really matters is the gaps in the ratio's and the spread of power in the engine matches the ratios.

[lms6201]

from memory didn,t one of the popular conversions of the yam tt 500 remove two gears ? i had an xt at the time and i remember reading about an aftermarket framed tt with only 3 gears 

[brent j]

N.E.B in England do a three speed gearbox for XT/TT's. I've no idea if, or how successfull they are.

[YSS]

Our Metisse 998  has in MX trim only 3 gears (roadracing and dirt track 5) and I ever only used two (1+2)
On the sidecar 998  (3 speed), I usually use only one gear . We take off in second , and with todays tracks , thats all you can use.