Suspension advice please | GTAMotorcycle.com

Suspension advice please

smudger

smudger

Well-known member
Ok, I hope this all makes sense, here goes & I hope it's in the right forum as I only ride on track & I'm a mediocre green group rider.

Bike is 1991 Zx7J with OEM front forks that have just been rebuilt with new seals & oil but still same OEM internals.
Rear shock is Penske unit & to be honest the preload is wound pretty well down & it'll go to Mr Sherrard or someone similar for a rebuild & new spring? over the winter
I run Q3 tires &'the rear seems to have a ridge or prominent raised rubber forming on the back of the tread grooves at the cornering part of the tires when looking at the rear tire at top dead centre.
I'm a biggish guy weighing at 240lbs.
I want to maximize the set up I have & try to improve my track riding starting at TMP this Saturday.

Sooooo, Just checked my "sag" & results are below:

Front: using zip tie on forks, no load on forks = 0mm
Free sag, just the weight of the bike = 20mm
Static sag, rider & bike = 41mm

Rear: no load on shock = 0mm
Free sag, just the weight of the bike = 5mm
Static sag, rider & bike = 28mm

How do the above figures look to the experienced guys & do you recommend any changes?
I've been watching video's, reading posts etc but also thought I'd try posting here.
Apologies for the long winded post though.

Thanks, Smudger
 
Last edited:
I get the feeling of excessive front end dive, bike feels pretty stable through the corner (but I'm also pretty slow)
On the corners I have hit fast I do get the sensation of a gentle wallowing movement.

I'm just trying to get some baseline settings & work from there.

I also changed the front brake pads to EBC HH's from the old ones that were in the bike when I bought it - I'll do the 5 or 6 straight line runs off the circuit at Cayuga Saturday braking from 60 to 20kmh to bed them in.
I know there's better pads out there but these were in stock at my local store & I wanted to have fresh pads in for Saturday.
After watching videos of "Dave Moss" on You Tube I'm thinking about backing off the rear preload to give 32mm static sag & increasing front preload to 35mm static sag & then going from there.
 
2 things....there is nothing wrong with ebc HH pads. they work well and I have won races on them. second why are you so worried about the susspension? are you tearing tires? are u crashing alot? I see alot of this kind of thing where people get caught up in any aspect of what they "need". more power, better suspension, the new trick part ect. Why not just ride the bike till your fast enough to out ride it and just enjoy. if your really slow like you say your slight setup problem arent going to make any difference. good luck and have fun in the track and dont get stuck in your head
 
Snipes20 said:
Good luck and have fun in the track and dont get stuck in your head
Click to expand...
For sure overcoming the mental side & having the confidence in myself & the bike is a part of the problem for me.
Front tire looks nice but yea, I am tearing the rear tire & I do seem to crash a bit but both were the front end letting go & can 90% be attributed to cold tires on a cold circuit.
 
smudger said:
For sure overcoming the mental side & having the confidence in myself & the bike is a part of the problem for me.
Front tire looks nice but yea, I am tearing the rear tire & I do seem to crash a bit but both were the front end letting go & can 90% be attributed to cold tires on a cold circuit.
Click to expand...

your suggestion to adjust sag to 30mm rear and 35mm front may/should improve things, even 34mm on the front is ok

what bothers me is saying you crash a bit with the front end letting go and 90% can be attributed to cold tires/track. don't blame the tires. you need to look honestly at yourself and what you did to crash. "did i enter the turn too fast?" "should I have braked sooner and used less trail braking?" thinking is the best thing you can do. if you just blame the tires/conditions and don't think through what you did to crash it will be difficult to improve your riding - know what i mean? you knew conditions were cold with less grip. stay positive, and treat crashes as a learning process. work on smoothness and lines b4 speed.

EDIT tire pressures are very important and must be checked.
 
Last edited:
Set sag, if you don't know the numbers for your bike ask a professional to do it for you, ensure your suspension is well maintained and go riding, have fun and everything else will follow.
 
Can someone diagnose my tire wear? 22 laps.



There's at least 5 things that need to be considered with tire wear. Pictures on the internet is really the worst way to do it.
 
Last edited:
dricked said:
There's at least 5 things that need to be considered with tire wear. Pictures on the internet is really the worst way to do it.
Click to expand...
I'm not trying to be sarcastic. Point taken on using images to determine the problem. What are the five things to be considered?
 
Ask Kellen, it's always Rebound ...




dricked said:
Can someone diagnose my tire wear? 22 laps.



There's at least 5 things that need to be considered with tire wear. Pictures on the internet is really the worst way to do it.
Click to expand...
 
JoeyB said:
I'm not trying to be sarcastic. Point taken on using images to determine the problem. What are the five things to be considered?
Click to expand...

Track temperature, tire age (heat cycles/laps), tire pressures (cold or off the warmers and hot off the track), tire compound, rider pace,and how much of your suspension travel is being used, are all important factors and I'm sure I'm missing some. I'm not a tire diagnosing expert but those are all questions that are going to be asked.

boyoboy said:
diagnosis: szoke let some air out of your tire when you weren't looking.
Click to expand...

Lol

ZX600 said:
Ask Kellen, it's always Rebound ...
Click to expand...

kellen said:
Haha, or having a 2662 mounted when you thought it was a 7455
Click to expand...

It started to rain which cooled the track off enough that a 7455 would have lasted longer (18 laps and I had nothing left) but I also needed a slightly stiffer spring which I didn't have and there was also another diagnoses that wasn't possible to fix track side which may have helped.

OP, set your sag aroind 30-35mm. I would also consult a suspension tuner and have your equipment refreshed. If you don't know when it was done last, it's due. Have fun!
 
dricked said:
Can someone diagnose my tire wear? 22 laps.



There's at least 5 things that need to be considered with tire wear. Pictures on the internet is really the worst way to do it.
Click to expand...

There's a green towel duct taped to the right foot peg. Coincidence? I think not.
 
You must log in or register to reply here.

Back
Top Bottom