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View Full Version : Rear lifting up (ZX250R)



blue eyed savage
19th August 2008, 17:13
when u get to hard on the stopps my mates bike ( zx250r c 1999) the rear wheel lifts of the ground, how can i fix this.

sinfull
19th August 2008, 17:20
when u get to hard on the stopps my mates bike ( zx250r c 1999) the rear wheel lifts of the ground, how can i fix this.

Take the pads out the front calipers !

imdying
19th August 2008, 17:29
Once you lose the front and skate along on your face, you'll find the problem clears right up.

blue eyed savage
19th August 2008, 17:30
i got i vid of it, you cant tell but the when im trying to stop the rear is just skiming the ground. and dont tell me, its poor riding too i know

blue eyed savage
19th August 2008, 17:31
http://nz.youtube.com/watch?v=lFyn6488CUQ

sinfull
19th August 2008, 17:34
temp NZer ! Oh wait thats someone elses line !

blue eyed savage
19th August 2008, 17:35
so about trying to fix the problem

sinfull
19th August 2008, 17:39
so about trying to fix the problem

Take the front pads out !

sinfull
19th August 2008, 17:41
Or you could practice a bit more and get it right !
<object width="425" height="344"><param name="movie" value="http://www.youtube.com/v/-3PoMXZs1TU&hl=en&fs=1"></param><param name="allowFullScreen" value="true"></param><embed src="http://www.youtube.com/v/-3PoMXZs1TU&hl=en&fs=1" type="application/x-shockwave-flash" allowfullscreen="true" width="425" height="344"></embed></object>

The Stranger
19th August 2008, 17:42
Pillion a fat chick.

justsomeguy
19th August 2008, 17:42
Learn to brake more progressively and smoothly. Even at race track speeds the same rules apply, except then you will be braking at a faster rate.

http://youtube.com/watch?v=L8pnaRpDU1A

TimeOut
19th August 2008, 17:43
Don't squeeze the right hand so hard.

Or the front suspension could be past its use by date.

AllanB
19th August 2008, 18:06
All it is is too much pressure on the front brake when stopping - you are yanking it on too hard and the bike is stopping so fast that it starts to rotate up around the front wheel axle with the weight transfer - basically the arse end of the bike is catching up with the front - its called a stoppie.

Yank it on too much and it will flip right over the front.

If you are really stupid or skilled (read was stupid many times to learn this and now is considered 'skilled'...) you can do a smoking stoppie with a locked front wheel.

Personally I like to keep both wheels on the ground when riding.

Do a u-tube search for stoppie and you will find the following:

a. Americans do not know what saftey gear is
b. Americans, after doing something very wrong then post a video of it for the world to see.

blue eyed savage
19th August 2008, 18:12
ok so that was just stoping to fast? i can do stoppys just not good ones and i dont want to do them any more or bad things will happen.
i still think the back end fells light comepead to my bike but if theres nothing i can do so be it

fatzx10r
19th August 2008, 18:12
you could try breaking sooner and keeping to your side of the road :Oops:

blue eyed savage
19th August 2008, 18:13
yea my bad

Robert Taylor
19th August 2008, 18:20
when u get to hard on the stopps my mates bike ( zx250r c 1999) the rear wheel lifts of the ground, how can i fix this.

The damper rod forks in that bike are too soft in terms of low speed compression damping and also the spring rate is too soft. 70% of the problem is attributed to very weak hydraulic control and 30% or so to weak springing.
As the front end is blowing through its stroke with very little control that means oversudden weight transfer which unloads the rear. At racetracks we spend a lot of time dealing with braking pitch control, this issue is just as relevant with road going bikes as so many have abysmal control, especially with bikes such as that ZXR etc. Moreover how many people have fallen off such bikes over the years because of the limitations of the front ends?
As someone else said braking more smoothly will minimise the issue, but just imagine being able to brake with less need for such finesse and appreciably later simply because the front end is sorted out.....
In the end event its a choice between sorting it out properly or rather less than successfully fudging it with a cheap but rather less effective bodge.

piston broke
19th August 2008, 18:37
r taylor,
nice answer,
you are a bit far away from me,is there anyone in auck - whangarei,that u would recomend? that could sort out the duc suspension for me

Robert Taylor
19th August 2008, 19:48
r taylor,
nice answer,
you are a bit far away from me,is there anyone in auck - whangarei,that u would recomend? that could sort out the duc suspension for me

We get suspension units couriered to us frequently. PM me and I will elaborate. We have worked on that model / type of Ducati forks a number of times.

Katman
19th August 2008, 20:12
http://nz.youtube.com/watch?v=lFyn6488CUQ


What a fuckwit.

blue eyed savage
19th August 2008, 20:29
yes i know but i gess you just have to say it one more time dont u, i mean ur riding is perfect all the time.

racefactory
19th August 2008, 20:35
hey blue eyes savage,

interesting question... some stupid responses about braking less hard etc but we got there in the end.

Interesting to see the final answer and that the front is compressing too hard and quickly from low spring rate.

You going to sort it out? I guess you could brake a lot harder with some traction in the back wheel! Not to mention safer as you could emergency stop so much harder without losing the front as you'd be distributing the grip to the rear!

blue eyed savage
19th August 2008, 20:41
yes i think this is worth looking into more now. just looking on the net about it and i road it in the wet once and its a real handfull so my mate does need to get it sorted

blue eyed savage
19th August 2008, 20:48
im thinking new springs and oil? sound about right

Robert Taylor
19th August 2008, 20:48
yes i think this is worth looking into more now. just looking on the net about it and i road it in the wet once and its a real handfull so my mate does need to get it sorted

Be careful what you read on the net as so many ''put in their two cents worth'' and actually offer nothing useful. How many answers on this thread have ( aside from generally good natured fun ) actually given you a plausible answer?
My answer costs money to enact but ( in fear of being maligned as arrogant ) is actually the correct answer.

Robert Taylor
19th August 2008, 20:51
im thinking new springs and oil? sound about right

Like I said 70% hydraulics. Just fitting springs alone only sorts out 30 to 40% of the problem. PM me for a full answer or as you are in Taranaki come and see us so I can show you the full solution first hand.

blue eyed savage
19th August 2008, 20:59
are u open on saturday?

Robert Taylor
19th August 2008, 21:30
are u open on saturday?

Thankfully no, see too little of family as it is and in any event at Manfield on Saturday. 8.30 to 630 and often beyond, weekdays.

Katman
20th August 2008, 09:55
yes i know but i gess you just have to say it one more time dont u, i mean ur riding is perfect all the time.

You want me to "be nice" - ok.

Change your riding habits or you'll end up being a corpse long before you ever get the handling sorted on that bike.

sinfull
20th August 2008, 10:10
temp NZer ! Oh wait thats someone elses line !


What a fuckwit.

Hehehe Hi was wondering when you'd see that !




im thinking new springs and oil? sound about right


Like I said 70% hydraulics. Just fitting springs alone only sorts out 30 to 40% of the problem. PM me for a full answer or as you are in Taranaki come and see us so I can show you the full solution first hand.

Yeah don't rush in thinking its just a heavier oil and springs ya need ! The bikes prolly build to ride easy like, where the suspension handles it ok but like any bike (triumphs just as bad) if ya gonna ride hard ya gonna need to revaulve, respring and prolly look at the back as well !


Thankfully no, see too little of family as it is and in any event at Manfield on Saturday. 8.30 to 630 and often beyond, weekdays.
See if ya cant talk him and his mate into going to manfield for a look ! Coax them into riding on the track as apposed to that show on the vid !
I aint no saint when it comes to taking it easy (feel i need to upgrade the triples suspension also when i have the coin) but that was an apt description that Katman used with regard to that vid BES

avgas
20th August 2008, 10:23
the easiest way i have fixed this is by applying a thin layer of Silicone spray on the discs. This prevents you from flipping the bike

nodrog
20th August 2008, 10:47
the easiest way i have fixed this is by applying a thin layer of Silicone spray on the discs. This prevents you from flipping the bike

i nominate you for Mentor!

avgas
20th August 2008, 11:24
i nominate you for Mentor!
I try my hardest to help Darwin out

avgas
20th August 2008, 11:28
so about trying to fix the problem
Its on the bike?

MIZXR
22nd August 2008, 04:52
fuck I agree with Katman, your gona die if you don't wake up.

Sit back further on the seat will stop the back comming up --- somewhat.

find a nice smooth road or carpark and practice. One day you will need to know just how hard you can brake. Thou nice to see your not afraid of the brakes, but don't try this comming up to corners or you watch the bike sliding towards a car.
Learn the limits at a certain point any bike will do this then, when you find lots of money, get the forks rebuilt.

Learn to bring the back up at about 80 KPH and roll along on the front wheel before putting the wheel back down before you come to a stop- but try not to fall off, rolling stopies hurt bikes. Rolling the stoppie:Police: also don't hurt the bike as much as a lowly stoppy and are much more impressive.

Better to show off around town too.