Clutchless shifting

[quickbuck]

Question though can you roll start without a clutch, as once my clutch cable broke and me and a mate would not think we could do it. Opinions, observations, or anything on this one

Yep, my mate had to do it on a Ducati Paso.
Had to laugh when my missus (of the time) fell flat on her face after it fired.
Lucky she was in full kit, so the helmet prevented her face getting smashed into the ground of the service station at Picton. Getting on and off the ferry, and the ride to Palmerston North was a real adventure.

Problem: Clutch master cylinder seals blown.

Yep, took a bit of skill, and clutchless changes were the least of his worries.

[quickbuck]

Motorcycle gearboxes are of the sequential (constant mesh) design and will shift up and down happily with out the clutch...

Finally, somebody said it.

constant mesh. Says it all (and is printed on most sales brochures).

[quickbuck]

If you have a centre stand u can put the bike on the centre stand (or the reafr wheel stand if you're really crusty). Start up in gear . Then rock the bike off the stand with a bit of throttle on and hang on tight.

This was the way we used to wheel stand the CT90.

Was a bit harsh when it came back down though... (stand still down).

Another way was to hold the gear leaver down, rev the nuts of it, and let it go. Big Wheel stand.... Thing died of a melted piston. I have no idea why....
Must have been the way my brother rode it..... LOL

[mops]

The reason they are rough on the down shift is that you haven't matched your engine and road speeds

Actually on my b250, shifting up without the clutch is very nice and smooth, all though i haven't tried at high rpm's/high load. it will downshift, but not as smooth, because engine is not very happy to rev up to match speed of the tyre (in lower gear), which normally results in slippage of rear tyre (unless i do it at very low rpm's).

i heard people saying - you have to match the engine speed to the road speed.... and I'm thinking... how do you do that ? you are engaged on gear (so it is matched and you cant do anything about it), you force it into lower gear, without going into neutral... straight onto another gear and by then you expenct the engine to by in sync with the road ? and like how is this supposed to happen ?
so how do you exacly match the engine to road speed ?

[DMNTD:Me]

clutchless up shifting is totally fine....won't harm your gear box at all....

My gearbox is currently being replaced after its 4th gear farked out.
They(Kawasaki dealer and Kawasaki NZ) are claiming that it was due to me clutchless changing.
As I've never changed down without using the clutch it would appear that maybe there could be damage incurred.
Dunno...hence why I give my bike to mechanics

[Manxman]

My gearbox is currently being replaced after its 4th gear farked out.
They(Kawasaki dealer and Kawasaki NZ) are claiming that it was due to me clutchless changing.
As I've never changed down without using the clutch it would appear that maybe there could be damage incurred.
Dunno...hence why I give my bike to mechanics

Can anyone definitively advise whether clutchless shifting is poss on a '93 250 Bandit? I seem to be doing inadvertently every now and then, but not sure if this is causing any damage...obviously don't want to end up with an expensive repair...
Thanks.

[Manxman]

My gearbox is currently being replaced after its 4th gear farked out.
They(Kawasaki dealer and Kawasaki NZ) are claiming that it was due to me clutchless changing.
As I've never changed down without using the clutch it would appear that maybe there could be damage incurred.
Dunno...hence why I give my bike to mechanics

Can anyone definitively advise whether clutchless shifting is poss on a '93 250 Bandit? I seem to be doing inadvertently every now and then, but sure if this is causing any damage...obviously don't want to end up with an expensive repair...
Thanks.

[Ixion]

Clutchless shifting up or down on any gearbox is possible. If you are clever enough at rev matching. Whether it is a good idea is another matter. Without the clutch as soon as the dogs engage the whole of the engine inertia and the bike inertia will meet head to head without the cushioning effect of the clutch. That can put a fair shock load on the gearbox components. You won't usually notice it , but the gearbox still has to suddenly take up a whack of torque (one way or another) without any cushion .Except the chain, unless you have a rear cush drive or one of the old engine shock absorbers.

Over time the combined effect of those loads can cause damage. Also, the box will take up as soon as the edges of the dogs engage . (A) that can cause wear to the dog edges (slipping out of gear eventually) and (B) the selector mechanism may be put under extra laod as it has to slide the dogs the rest of the way into engagement when there is a drive (or driven) force loading the mating faces of the dogs.

Some boxes can take it indefinately. Some can't. Clutches are there for a purpose.

[Manxman]

Thanks Ixion. I guess I'll play safe and carry on using the clutch...

[quickbuck]

I have found that my Hondas are better at it than the Suzukis I have owned.
I put it down to a higher quality motorcycle.

As for matching the engine revs to the road speed on the down shift (in a question above), it is easy. That is one of the uses of a tacho.
All you do is think, okay, I'm doing 5000rpm in top, and I am about to slow down (why else would you be changing down, on anything bigger than a 400) so in the next gear, I will still need about 5000rpm (or a bit less.. depending how much you are slowing down), so ensure your revs are about that...

In saying all that, i never do clutchless down shifts, because it usually goes...Righto, braking maker... Full application of both brakes (Note weight of foot is enough for rear), at same time, clutch in, chop down to gear i need to be on exit... clutch out Gas (try to make it full throttle.. if back starts to slip, ease off a bit).

Yeah, you got me... This isn't how I ride on the road, I am just looking foward to Manfeild on the 5th.
Weather is sh1t today, Christmas function after work (one of 7), so bike will spend the weekend here.

Have a safe one all..

[dipshit]

so how do you exacly match the engine to road speed ?

By blipping the throttle on downshifts.

....

(edit) Holy christ, i didn't realise this thread was so old!

[CookMySock]

i didn't realise this thread was so old!

haha, a common forum-newbie error..

Steve

[Katman]

Clutchless shifting can accelerate gearbox wear especially if the shifting is done on positive throttle instead of a coasting throttle. The gear dogs are forced to slide across the gear mating face under load eventually causing an angled mating surface and the tendency for the gearbox to want to jump out of gear.

[<Rhino>]

By blipping the throttle on downshifts.

....

(edit) Holy christ, i didn't realise this thread was so old!

Neither did I, but I read it in anycase and still learned somthing. Tried it out on my bike and in some situations its actualy pretty damn handy.

[DarkLord]

This is all well and good, but what if your clutch cable snaps when the bike is at a standstill and you are stuck in first (I always leave the bike in gear)?