downshifting skids :( suggestions?

[scott_blah]

Well I'v currently got a Pitpro 150XR (they're a lifan 150 for those not in the know) and so far I havnt had any problems with it. bit of a pain to put together and little things like that but hey what do u expect for just over a grand, and my god does it haul!!!!
My main issue is the downshifting skids. you need to let the revs drop hellishly low before you downshift, say from 3rd to 2nd, otherwise on tarmac it'll lock up the back wheels for a good meter and a half, which my kenda carlsbads really hate
not sure if its a gearing issue which could be resolved with a simple sprocket change or if its just compression.

this is my first pitty and also my first 4-stroke so excuse my noobishness

if anyone has any suggestions or solutions it would be wicked

cheers

 

[jakey]

my pit pro 125cc rr does that too i just slow down before hand lol

 

[scott_blah]

lol yeh i spose i could always ride a little easier but with a quite a few school kids living in my street i wanna look cool pulling into the drive at high speed quick downshifts

plus i would like to keep the kenda alive, they're a good tyre

 

[no_crf50_here]

1. Why do people ride on the dam road?
2. YouTube - Backing it in on a minibike at Archerfeild motard track control and enjoy.

 

[luclml]

i do that all the time to my friend has a honda 50 and he just uses his front brake while down shifting if u dont wanna skid try that it might work

 

[Pattyz]

Try holding the clutch at the point where it just engages after you've shifted down so you can make it into a more smooth motion.

 

[duff_boy]

rev match your down shift? pretty simple isnt it?

 

[scott_blah]

YouTube - Backing it in on a minibike at Archerfeild motard track control and enjoy.

so what exactly is he doing there in a step by step breakdown

 

[motoXXX]

the only reason it does this is because u dont know when to change gears,you dont be in 3rd tapped and then just all of a sudden drop it into 2nd that is just stupid and will screw your gear box and tyre in a flash you have to brake and then when you feel it is ok to change down by listening to the revs and the speed you are going you dhould be able to judge when and where to down shift...if you cant do that without locking the rear tyre up then you DO NOT! belong on a motorbike.

also dont lock your rear wheel up using rear brake without having the clutch in or that will screw your box super quick aswell...

 

[crazzy #1]

i see a bigger bike in your avatar, so obviously you know at what revs you should shift, but something that must be considered when riding a 4 stroke is that they have greater levels of compression! when gearing down on a 2 stroke the bike dosnt lock up nor miss behave unlike a 4 strokes, i find the easiest way to gear down smoothly is to slightly bring the revs up whilst pulling the clutch in and selecting a lower gear, i find giving it a quick squirt before releasing the clutch does the trick

 

[coolmodee01]

what gear ratio are you running
mine does it but mainly coming into corners hot
but i did find 2nd a bit short running 16-41 tooth ratio
chucked a 15tooth sprocket on the front and that made 2nd a bit longer and minimized the compression lock up

 

[Panda_ET]

oi scott learn to ride compression lockup ftl

get out on the trails u lazy KENT

 

[Cactus Jack]

LOL ... It's hard to fathom that there are dopes who downshift without rev matching (blipping the throttle) and using the clutch ... These bikes have wide ratio trannies and long stroke cranks so it's even MORE critical to upshift and downshift correctly ... otherwise you risk knocking teeth off the gears , busting dog lugs off , or simply cracking the cases ... When riding a 4 stroke , get all that sh*t you learnt from riding two strokes outta your head ... It's got nothing to do with the strength of the cases or engine parts but does have everything to do with the intellect of the rider ...

Going fast and changing gears quickly can be done skillfully WITHOUT abusing the clutch or tranny ... Deceleration is done in the reverse of acceleration ... to accelerate , you take the engine from low to high revs in each gear and on deceleration you take the revs from high to low in each gear ... fast 4 stroke riders do not chop the throttle fully into corners , and they also don't allow the revs to drop too low ... instead you match the revs to the gear ratio and speed of the bike thru the turns the same on dirt as you would on tarmac ... When you learn to ride like that ... you start to go faster and stop crashing ...

 

[BradZ_09]

Ive been told its called compression locking.
Example: Goin flat in 3rd, down to second with no brake. 2nd gear cant handle it.

Different speeds, thats what gears are for, just slow down a bit before you shift down

 

[motoluver]

Yeh Im back on a 2 stroke now. Havent rode a 4 stroke in ages.

When on 4 strokes pull the clutch in and the same time you shift down give the throttle a big rev and then let go of the clutch and no more locking up

 

[Sidney]

Yeah it's called blipping the throttle, you have to use it all the time on the road.

 

[Cactus Jack]

Ive been told its called compression locking.
Example: Goin flat in 3rd, down to second with no brake. 2nd gear cant handle it.

Man , how dumb assed is that !!!!!! You shift to 3rd in the first place because the engine has peak revved in 2nd and can't go any faster ... shoving it down into second from high revs in 3rd is a sure fire recipe to destroy an engine ... IF the rear wheel doesn't lock up , the engine will over rev , float the valves and the piston will smash into 'em ... I'll bet that's how a lot of dorks are stuffing their engines up ... You only have to float the valves just enough for 'em to tap the piston and they'll bend instantly ... especially with the scrawny little valve stem diameters horizontal engines run ... then they'll give a lousy seal at the seat ... the symptoms of which are popping in the pipe on deceleration ... and carb tuning problems ... Engines with perfectly sealing valves don't pop at all ... even if revved to over 14,000 + rpm and backed off hard in any gear ... and ALSO with an open exhaust pipe with NO muffler whatsoever ...

Some people think popping on decel is normal ... yeah right ... just listen to any F1 car kicking down thru the gears , a speedway car , solo bike , drag car , race boat or what ever ... the only ones you'll hear popping are on their way back to the pits with a stuffed motor ...

 

[sn33ky23q]

Man , how dumb assed is that !!!!!! You shift to 3rd in the first place because the engine has peak revved in 2nd and can't go any faster ... shoving it down into second from high revs in 3rd is a sure fire recipe to destroy an engine ... IF the rear wheel doesn't lock up , the engine will over rev , float the valves and the piston will smash into 'em ... I'll bet that's how a lot of dorks are stuffing their engines up ... You only have to float the valves just enough for 'em to tap the piston and they'll bend instantly ... especially with the scrawny little valve stem diameters horizontal engines run ... then they'll give a lousy seal at the seat ... the symptoms of which are popping in the pipe on deceleration ... and carb tuning problems ... Engines with perfectly sealing valves don't pop at all ... even if revved to over 14,000 + rpm and backed off hard in any gear ... and ALSO with an open exhaust pipe with NO muffler whatsoever ...

Some people think popping on decel is normal ... yeah right ... just listen to any F1 car kicking down thru the gears , a speedway car , solo bike , drag car , race boat or what ever ... the only ones you'll hear popping are on their way back to the pits with a stuffed motor ...

perfectly said lol

 

[numroe]

My main issue is the downshifting skids. you need to let the revs drop hellishly low before you downshift, say from 3rd to 2nd, otherwise on tarmac it'll lock up the back wheels for a good meter and a half, which my kenda carlsbads really hate

Use your brakes. Both ends. Pull in the clutch when you shift. Down shift at the right time. Not too early or too late. Shift too soon on decel and your problem happens. Shift too late and you lose accel out of the corner, or if you are after some engine braking and you shift too late - then you get none.

Mostly just learn to use your brakes and clutch more. If you must ride tar then practice front wheel endo coasting stops to improve front brake skills.

I've got the Lifan 150 too. It spins up fast enough on normal downshifts that your problem should not be happening.

 

[daimojay]

just learn to blip the throttle.... u have to rev match otherwise you wouldnt be able to brake as hard as your able to, nor down shift at the correct times...