Judder while braking ??

RQ · Post by RQ » Sat Oct 04, 2003 12:12 am

Back roads, enjoying the twisties etc........ corner onto a straight..........farmer............. tractor....... slow......... grabbing handfulls of the levers to try and stop before ploughing into the back of him and there was this odd shake in the steering.
I found myself a smooth bit of road and hammered on the anchors to see what would happen, same, a little shake more forwards and backwards than left to right. No shakes under normal braking, only on the 'urgent' stuff. So here comes the question.... how do I know whether it is a problem with suspension or a problem with the head bearing without dismanteling the bike ??!!?? (Bearing in mind that the car is off the road at the moment, and the storm is my only mode of transport !!)
Ronan.

chromedome · Post by **chromedome** » Sat Oct 04, 2003 11:51 am

Ronan
I have recently had a similar problem with my 'Storm. I bought a 2nd hand pair of cast iron disks, and under certain braking conditions - usually prolonged braking at high speeds - I got the judder you describe. I guessed that it was either a warp getting more pronounced with heat build-up, or some problem with the disk float. I rulled out loose head bearings by raising the front and trying to move the forks back and forth.

I replaced the disks with a new set of PFM Supersport disks, and the problem was cured, and braking was much improved over standard. They cost just under Â£300 for the pair.

Matt

delmeekc · Post by **delmeekc** » Sat Oct 04, 2003 8:03 pm

Just did Essexblokes bike and he had new wavey front disks and pads and a wavey rear fitted with new pads. Total would have been just under Â£350 but he had chain and sprockets too and a rear shock spacer. (That included fitting, cleaning caliper pistons etc and.)

We had to pop out for some bits and he was well impressed with the fronts (hadn't done the rear at the time) and they aren't even bedded in. He had the brake wobble/shudder etc, all gone now.

Del.

RQ · Post by RQ » Sat Oct 04, 2003 11:49 pm

Thanks guys,

I'll try checking the bearings by raising it, and I know the disks are a bit out, but never thought it would create such a reaction when braking ! At least it may not be expensive !!

RQ.

Stormin Ben · Post by **Stormin Ben** » Mon Oct 06, 2003 12:15 am

Have you got standard forks?
Sounds like it could be bottoming out as its only during extra hard braking, not in normal use
Just a thought

Ben

essexbloke · Post by **essexbloke** » Mon Oct 06, 2003 8:46 am

See del's post above.......

mine juddering was that bad, the fillings were coming loose..........

full set of new disc's/pads later.........not a thing.........

nobbyk · Post by **nobbyk** » Mon Oct 06, 2003 6:11 pm

I think it may be forks too! You will get some patter off the road surface when braking, and, if the forks are at the bottom of their travel it will tranfer that straight up the fork and on too the bars.

Sometime ago, I changed my fork set up to match P/Bikes settings. Whilst I did not have to much of a problem with braking, the front end was much more stable under accelerating and braking. I'd check the tyre pressures too. Every little bit makes a difference when pushed to the limit!

Regards

Nob

RQ · Post by RQ » Mon Oct 06, 2003 9:37 pm

Thanks for the responses !

I have standard forks, and now for the really stupid question

, how do I stop them bottoming out !! I'm guessing it has to do with the adjustment at the tops of the forks, but which way, and how much ! Sorry, of all things, suspension is not my speciality !

RQ.

chromedome · Post by **chromedome** » Mon Oct 06, 2003 10:27 pm

Adding preload will help. The preload adjusters are the cylindrical raised parts with evenly spaced rings running down them, and they have a damping adjuster screw in the middle.

Winding them in, so there are less grooves visible, will mean that it takes more force to bottom the forks out. A recent Performance Bikes suspension guide suggested that having anything from ring two (from the top) to fully wound in is suitable for fast road/track riding. The damping should be 1/4 turn from full in.

The standard forks are renowned for being crap - too soft. My own forks were rebuilt by Maxton Engineering for Â£210 making a huge improvement, and I gather that the guys at Revolution Racing can transform pretty much any aspect of the 'Storm.

nobbyk · Post by **nobbyk** » Tue Oct 07, 2003 4:28 pm

Hi RQ

As I said before, the PB settings are a good start before you go spending money, they almost make a silk purse from a sow's ear, well, you know what I mean.

I have no doubt someone on this site has the settings or can give you a site addy to get them. mine were lost by my wonderfull Ninja lovin bastid bruvver! soz mate.

regards

nob

Martin · Post by **Martin** » Tue Oct 07, 2003 8:06 pm

shamelessly taken from the PB suspension setup supplement:

Rear Shock: Preload - Road position 2
Track position 3

Rebound - 1/4 turn from FULL IN

Front Forks: Preload - Road groove 2
Track FULL IN

Rebound - 1/4 turn OUT from FULL IN.

Hope this helps.

Martin

RQ · Post by RQ » Wed Oct 08, 2003 5:05 pm

Thanks loads guys ! I'll try those settings over the weekend and I'll post up how I get on !

RQ.

nobbyk · Post by **nobbyk** » Thu Oct 09, 2003 6:06 pm

Martin

I thight the rear preload was actually 1 from 2. I could be wrong!! It's a bleedin hard spring as standard.

Nob

Martin · Post by **Martin** » Thu Oct 09, 2003 11:27 pm

I haven't got a clue when it comes to suspension etc....I've been riding round with a shagged headrace for the past few weeks and didn't really notice!!!! (can tell now it's fixed though!) Just copied out what the wee book said, but don't know where I've put it now so can't check!

nobbyk · Post by **nobbyk** » Sat Oct 11, 2003 1:54 pm

Martin

When I lived in Crawley Down village(not far from you) I couldn't find a bleedin Storm rider to rideout with for love nor money.
I moved up here in July and now you all come out of the bloody woodwork !

Cheers

Nob

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Judder while braking ??

Judder while braking ??

Susp settings