I don't know much (ok, nothing) about motorbikes, but is it really so easy to select the wrong gear at the wrong speed, with in this case tragic consequences?
As a layman I'd have thought there'd be some kind of mechanism to prevent it. I know you could do it in a car but the results are less likely to kill you I'd have thought.
Or do big expensive bikes have a preventer and cheap ones that teenagers ride don't?
www.cambridge-news.co.uk/Home/Gear-switch-error-led-to-fatal-crash-for-motorcyclist-04042012.htm
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Motorbikes have sequential gearboxes, operated by a foot lever (usually left hand side), and you move this foot lever up or down to select the next gear in sequence. You cannot "skip" gears, so if you want to go from 4th to 1st, for example, you must go through 3rd and 2nd to get there. Each change involves moving the lever, and then allowing it to return to its rest position, so the example above would require three distinct movements of the foot.
The sequence on most bikes, starting from the "bottom", and requiring an upwards movement on the gear lever is 1, N, 2, 3, 4, 5, (6 etc)
Last edited by: DP on Wed 4 Apr 12 at 09:24
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>> Motorbikes have sequential gearboxes...
So how could he have put his bike in the wrong gear? From DP's clear explanation it doesn't even look as if he could have gone from 2nd into 1st instead of 3rd. What could have caused the rear wheel to lock?
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Sorry, you could go from 2nd to 1st. Neutral is the only exception to the rule in that you go "through" it between 1st and 2nd, or 2nd and 1st. The lever will move in two distinct "notches", the first being neutral, and the second being the next gear. One foot movement in any of the other gears will only ever select the next gear in either direction.
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Understood. I suppose going from 2nd to 1st at the upper end of the engine's rev range might cause the wheel to lock.
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He'd have had to stamp on it I would reckon unless there was a fault present - It's not something that easily done - dunno how much having his helmet undone actually led to his death though. Sad loss seems to have been a decent lad.
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I've certainly done it by mistake, changing down rapidly for a junction. Selected 1st at far too high a speed, but without the tragic effects the DP suffered. Youthfull inexperience I suppose. Apparently some machines have a "slipper clutch" which reduces the amount of engine braking to cut tyre chatter or lock-up. Never come across this personally but then my last bike was made in 1966....
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When I rebuilt an old Honda 500 twin, I missed a shim out of the the gearbox - found on the bench after clearing up.
That won't matter, I thought to myself.
Er, it did. The gearbox had a habit of jumping out of 2nd gear back into neutral unless you kept your foot under the lever.
Bit hairy when giving it a fistful and jumping back into neutral while accelerating.
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I would hope that someone did at least check that this (or something like it) wasn't a known problem on the type of bike involved in the accident.
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>> The sequence on most bikes, starting from the "bottom", and requiring an upwards movement on
>> the gear lever is 1, N, 2, 3, 4, 5, (6 etc)
>>
That's a Japanese thing. British bikes were always up for 1st, then down through the box (usually for a total of four gears - 1 up, three down), although I think that most have gone to the Jap system these days. Indian Enfields were still using the British system last time I looked.
The British system makes it impossible to stamp on the lever and accidently change down. Changing to a higher gear is less of an issue as it will not cause the rear wheel to lose grip.
The other factor to complete the picture is that British bikes (and Indian Enfields) have the gearshift and rear brake on the opposite sides to the Japanese system. Thus a rider used to a British bike swapping to a Japanese or modern machine can easily go for the rear brake in a hurry as an instinctive action and produce an unexpected downshift (sequential 'bike boxes will easily change down with the clutch engaged given enough "oof" from the rider's leg). The combination of a situation requiring emergency braking and an unplanned downshift breaking rear grip can easily result in loss of control.
I knew a bloke who upgraded from an Indian Enfield Bullet to a Kawasaki 500[1] and put it into a hedge doing just that, which leads me to wonder if........
[1] Scarily quick for a 500 it was too.
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Just to clarify modern,properly developed and properly engineered Triumphs comply with Japanese norms !
I had custody of a Honda125 (Think it was an yr 2000 bike from memory) had the 1 up 4 down gearbox, it was an oddity, It had MPH speedo a Km Odo - and was made in Japan....
A good machine for focusing the mind when riding.
Just to clarify most Honda 125s are made in Brazil and other third party countries. This bike had a Mandarin Chinese handbook but was a "genuine" grey import through a very reputable dealer.
Last edited by: R.P. on Wed 4 Apr 12 at 11:46
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>>
>> I had custody of a Honda125 (Think it was an yr 2000 bike from memory)
>> had the 1 up 4 down gearbox,
>>
GP motorcycles have that type of box, it enables faster upshifts.
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I doubt whether this one would have won any GPs - one of the few ties I was actually overtaken by other stuff.
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>> Just to clarify modern,properly developed and properly engineered Triumphs comply with Japanese norms !
Rubbish, real bikes have always been one up, three down.
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Rubbish, real bikes have always been one up, three down.
The sort of attitude that consigned the old British motorcycle industry to the dustbin - and not before time.
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>> Rubbish, real bikes have always been one up, three down.
>>
>>
>> The sort of attitude that consigned the old British motorcycle industry to the dustbin -
>> and not before time.
It wasn't the gear placement that killed british bikes. Even so If i ever got another bike again is would be a 60's Bonneville.
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>> It wasn't the gear placement that killed british bikes. Even so If i ever got
>> another bike again is would be a 60's Bonneville.
You would enjoy stopping every 100yards to pick up the bits that just fell off???
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Lighter and more agile than its current namesake it was, but it couldn't keep its oil inside itself and was made by a load of shiftless waters. They are now in the premier league of international makers - they never made it to the Sunday league before.
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Yeah it was a bit weepy, but was basically reliable and a great bike to ride.
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>> That's a Japanese thing. British bikes were always up for 1st, then down through the box
IIRC, only the Yamaha FS1E (Fizzy) had a selector that was 4 down. All other Jap bikes had 1 down, and the rest of the gears up, going through neutral between 1st and 2nd.
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Apart from my odd Honda 125 ? (It was a genuine factory design - there was a schematic in the Handbook !)
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It would be quite easy for an inexperienced rider to do this, as others, I have done it myself at slow speed and locked the rear wheel (as the clutch is released) when approaching a roundabout in the wet. It's one of those things that can only be sorted through practice.
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>> Apart from my odd Honda 125 ? (It was a genuine factory design - there
>> was a schematic in the Handbook !)
>>
Dis it have rearsets?
IIRC some bikes simply reversed the gear lever when the pegs were moved back - thus turning the shift pattern upside down.....
Proper bikes had a linkage of course.
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Rearsets...?
No, what it did have was the Honda stepthrough type gear selector, where the whole boot sat on "dual" but linked gearchange. Most bizzare but allowed quick gearchanges when you got your head round it.
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>> Rearsets...?
>>
>> No, what it did have was the Honda stepthrough type gear selector, where the whole
>> boot sat on "dual" but linked gearchange. Most bizzare but allowed quick gearchanges when you
>> got your head round it.
>>
Rearsets was what we called a mod, where the footpegs were mounted further back that factory position....
(still available) www.fasterbydesign.co.uk/CRG_rearsets.asp
The link shows a proper set... some back in the days were knowt more than a bodge!
Hmmmm yes those rocker selectors are fun.... great when you get used to them though.
I remember having to 'teach' my Dad to ride a Jap bike.
He had AJS's in his day, then got a Kawa when he was about 54.
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Sad loss, and I suspect the police are on the money with the cause. One of those things you learn by hard experience in your formative biking days, usually only with embarrassing rather than tragic consequences.
At one time I had the following stable of bikes on the road;
Harley WLA (3-speed hand change with foot clutch on left, rear brake on right)
Triumph 3TA ( right-foot gearchange, left-foot rear brake)
Honda CD175 (left-foot gearchange, right-foot rear brake)
Normally I could go from one to another with little difficulty, but the occasional lapse of concentration led to the odd hiccup, thankfully minimised by all three having pathetically weak front brakes making a front-end lock-up almost impossible!
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I thought I had it hard HM, swapping from the BMW's linked, power assisted ABS, computer controlled brakes to the Kwaker's basic front rear jobbies !
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>> I thought I had it hard HM, swapping from the BMW's linked, power assisted ABS,
>> computer controlled brakes to the Kwaker's basic front rear jobbies !
>>
Try half-width 8" cable-operated drums (with front brake lever on the LEFT bar if you want it 100% pukka!) manual advance/retard, hand change, foot clutch and a throttle with no return spring! Believe it or not the old Harley 45's are childishly simple to ride once you've got the hang of it, though tight left turns up a gradient are best avoided unless you've got the optional auxiliary hand clutch or are very experienced.
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Gears on the Velo are 1up, 3 down on the right. I have learnt to change from 4th to 1st very qwickly in 3 rapid lifts of the foot. This procedure is essential if you need to stop in a hurry due to the engine braking being a lot better than the pathetic half width 5 inch drums, cable front and rod rear. That's the sort of machine to get roadcraft experience on.
As a teen, I had another Jap variant, a small Suzuki with a rotary gearbox. You just kept pressing the pedal down and it went round all the gears in turn and back to 1st.
The current steed has a sort of variomatic box, no clutch or gear lever. Back brake is the left handlebar lever with the front on the right with a delayed link to the rear. Both discs. It's pretty good at the traffic lights grand prix, getting off the line to 60 in 5 seconds.
This'll be my last modern bike...it does fine for me.
Ted
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Heres a trick i tried once on my cb 750, i reversed the gear lever so it could be operated
with my foot whilst it was resting on the pillion foot peg , making it 1 up and 5 down
and i never screwed it up.....it gave one a more streamline position using the back pegs
but when slowing down the right foot had to move smartly to the front peg to actuate the rear brake pedal......crazy times
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Motorbikes and 1st gear - DP
