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M.A.M. Racing team
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Thanks all for the help and suggestions! You as well M.A.M, I will be looking at that sag number in the front. Here's the update from last weekend's race. From the get-go, the bike felt great. It took most of the Friday trackday to get used to the changes, trying different areas of the track here and there. But, by Saturday's race, I was very comfortable and the bike felt dialed in! No more front end issues. It felt great and no bottoming out under hard braking, and I still have 20mm of travel to play with!

By race two the rear needed a little tweaking. It was tearing up the new tire pretty fast. I removed one turn of preload and two turns of rebound. It cleaned up pretty quickly. But other than that, the bike was not sliding nearly as much, and I felt very confident coming out of the corners. There was a little sliding, but very predictable. I did 1 practice session, qualifiying and 2 six lap races and the tire was done. Although, I did take a 1st and 2nd place in both races and put down a personal best time of 1:52.9, which is a time of most experts, and I didn't fell out of shape doing it. I had to chase down 1st place, but I caught him with one lap to go and was able to hold him off (Brent) :yesnod

For Sunday's race, I had to put on a new tire for two more races. It was very windy and ugly so I wasn't pushing too hard. I almost took another first place, but barely missed and took 2 second places! Here's a picture of the tire after 1 practice session and 2 races. The track temp was kind of cold, but I was running a decent pace and the tire looks pretty good to me..

I also had a buddy that normally races a 600 take my bike out for a spin. He was throughly impressed how the bike handled. He said it tipped in easy, felt very stable under braking, cornered well, etc. That was great to hear from someone riding a smaller, more nimble bike!
Well done! Work on the front to get it to YOUR likeing and trust and then when you are done with that move to the rear. Work one at a time forget the sliding it is controlable for the time being,trusting the front is what makes you fast,when you get that forget about it and work on rear traction.Racers with rear issues in a race will more likely win the race that of a racer with front issues.So if you are comfy with the front then the rear setup will be a peice of cake :note, a ttx is hard to tune because its a high speed shock with a topout spring in it,You have to look at tire wear to understand what its doing, you cannot bounce a ttx a see a difference in the rebound stroke like other shocks,its a great shock if tuned properly.My setup for a ttx is 0.90spring 14mm installed preload with no additinal preload so it sits lower in the stroke and 305mm eye to eye shock length with a 200/60/17 Pirelli slick and the axcel further back and from there on i work with the damping....Good luck with your racing.The tire looks good from what i can see from the foto.
 

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M.A.M. Racing team
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19 Posts
Thanks all for the help and suggestions! You as well M.A.M, I will be looking at that sag number in the front. Here's the update from last weekend's race. From the get-go, the bike felt great. It took most of the Friday trackday to get used to the changes, trying different areas of the track here and there. But, by Saturday's race, I was very comfortable and the bike felt dialed in! No more front end issues. It felt great and no bottoming out under hard braking, and I still have 20mm of travel to play with!

By race two the rear needed a little tweaking. It was tearing up the new tire pretty fast. I removed one turn of preload and two turns of rebound. It cleaned up pretty quickly. But other than that, the bike was not sliding nearly as much, and I felt very confident coming out of the corners. There was a little sliding, but very predictable. I did 1 practice session, qualifiying and 2 six lap races and the tire was done. Although, I did take a 1st and 2nd place in both races and put down a personal best time of 1:52.9, which is a time of most experts, and I didn't fell out of shape doing it. I had to chase down 1st place, but I caught him with one lap to go and was able to hold him off (Brent) :yesnod

For Sunday's race, I had to put on a new tire for two more races. It was very windy and ugly so I wasn't pushing too hard. I almost took another first place, but barely missed and took 2 second places! Here's a picture of the tire after 1 practice session and 2 races. The track temp was kind of cold, but I was running a decent pace and the tire looks pretty good to me..

I also had a buddy that normally races a 600 take my bike out for a spin. He was throughly impressed how the bike handled. He said it tipped in easy, felt very stable under braking, cornered well, etc. That was great to hear from someone riding a smaller, more nimble bike!
Well done! Work on the front to get it to YOUR likeing and trust and then when you are done with that move to the rear. Work one at a time forget the sliding it is controlable for the time being,trusting the front is what makes you fast,when you get that forget about it and work on rear traction.Racers with rear issues in a race will more likely win the race that of a racer with front issues.So if you are comfy with the front then the rear setup will be a peice of cake. A ttx is hard to tune because its a high speed shock with a topout spring in it,You have to look at tire wear to understand what its doing, you cannot bounce a ttx a see a difference in the rebound stroke like other shocks,its a great shock if tuned properly.My setup for a ttx is 0.90spring 14mm installed preload with no additinal preload so it sits lower in the stroke and 305mm eye to eye shock length with a 200/60/17 Pirelli slick and the axcel further back and from there on i work with the damping....Good luck with your racing.The tire looks good from what i can see from the foto.
 

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I have noticed both here in the UK and elsewhere certain companies informing riders to set their racesag 25-30mm!

As MAM, Dan and I have mentikned with the correct springing you should be running a 33% racesag of total travel and you need to be aware full travel does not always mean to the fork bottom, many bikes mechanically top out above this, so be aware if you dont know what your bottom out is travel indicator tuning will not help.

MAM, anymore advice re ttx tuning, guess itll be like my WP4618 comp, sag numbers go out the window...
 

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M.A.M. Racing team
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19 Posts
I have noticed both here in the UK and elsewhere certain companies informing riders to set their racesag 25-30mm!

As MAM, Dan and I have mentikned with the correct springing you should be running a 33% racesag of total travel and you need to be aware full travel does not always mean to the fork bottom, many bikes mechanically top out above this, so be aware if you dont know what your bottom out is travel indicator tuning will not help.

MAM, anymore advice re ttx tuning, guess itll be like my WP4618 comp, sag numbers go out the window...
Yes indeed you have to factor in the mechanical bottom out on your forks for your sag reading.These are my numbers for the forks:140 total travel from the dust seal to the accel casting - .5mm bottom out =135mm divide in 1/3=45mm of sag or 33% of travel x 135=45mm For the rear i race two types of shocks,(1.ohlins ttx36)( 2.matris full race shock) both have a 100mm of rear wheel travel,100mm divide in 1/3=33mm or 33% of travel x 100 =33mmsag.Thats how i calculate my suspension by starting 1/3 of total travel or 33% (same result) front and rear and build up on that(its a safe spot).Remember my freind its all about rider prefrence. I have tried alot of setups with smaller numbers but lets not forget it puts you high in the stroke and more likley of topping out front and rear.Both front and rear settings are with the preload adjusters at fully soft and i work with oil levels and compression damping to deal with track conditions.
 

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Turn and Burn!
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Great advice M.A.M. I did take all those bottom out measurements and I think I posted them in this string. I'll look again. Thanks for explaining the 33%. You guys are talking way over my head but I do enjoying reading, tweaking things and learning!
 

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M.A.M. Racing team
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19 Posts
Great advice M.A.M. I did take all those bottom out measurements and I think I posted them in this string. I'll look again. Thanks for explaining the 33%. You guys are talking way over my head but I do enjoying reading, tweaking things and learning!
Preload makes the bike sit higher, or lower - it does NOT make the spring stiffer.

"So if someone tells you that you should reduce your preload to make the bike feel less harsh, they probably don’t have a clue" (GB). A spring's job is to be able to compress almost fully and then return to it's free length without any changes to length or rate. When you "preload" a spring it simply means you compress the spring with a load or adjuster before any load is put on the spring. So if you have a spring that has a rate of 1Nm per mm and when you assemble the forks you compress the spring (preload) 10mm with the adjuster backed right off, then that is "installed preload". The usual preload adjuster has a further 15mm of preload range, this means the total force you have stored in the spring is 25Nm. To make the fork move you have to exceed this load, and then the rate increases by 1Nm because that's the spring rate. What makes it feel more stiff is that instead of starting at 10Nm it starts at 25Nm because the one force is higher than the other. This is what gives you the feeling of a stiffer spring.Hope this give all our R1 riders out there an understanding of what the preload ONLY does.It raises the bike for geometry changes.Have a good day/evening guys.
 

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Preload makes the bike sit higher, or lower - it does NOT make the spring stiffer.
Trying to convey this information to riders can be testing at the best of times!!!

On another note if anybody has copies of service manuals for their forks or shocks could I please get a copy emailed to myself..?

I am trying to compile a library of service manuals, just for future reference...

I know most forks and shocks have the same principles but aftermarket stuff does have its own quirks here and there as I have found out with my own kit!

PM Me if you have any manuals you can send me...

Thanks in advance :)
 

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Welcome to the Forum! Good place to post first :fact

The first 5 posts or so are a step-by-step guide, but then we have a few years of related discussion based on what people have run into. Hope to see you sharing soon!
 

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UR Gator Bait!!
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Dan (and others),

I read this entire thread about 6 mos. ago and searched it today for static front/rear weight bias'. The only post I found was by "max the lion" who hasn't been online since mid 2013. I saw where he didn't note any adjustments to it after his subsequent TD's etc. I've read a few suspension books, which I need to reacquaint with but I'm also curious to know specific good setups for '09+ R1's. From what I've read 52/48% is the "magic number".

I'm currently at 49/51 with OE forks flush with OE triples, 1 tooth down front sprocket, and +7mm reaer ride ht. over stock. I've read SBU goes as high as +15mm in the rear but I'm not sure if they have fork extenders. My sag is 35mm front 25 rear Ohlins carts, and Racetech internals in the shock.

I know more rear ride ht will make turn in more difficult; however, I'd like more front end feel.
 

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Magic numbers, let me pose this to you...Magic for who?

The hardest thing I encounter is with racers, they want to run somebody else's numbers.
A rider needs real honest evaluation here, what do they want, why do they want it and do they need it, once this is established then you can look at a plan of how to accomplish the mission.

I assume you race buddy? I only assume because I'm looking at your sag numbers and asking myself are you with those numbers because of soft springs and need extra preload or are your springs good and after testing you find your current setup needs the extra preload.

I don't advocate raising fork legs thru the yokes unless you really need too, this is only because of how Dave Moss schooled me! Especially if you have a shock which has adjustable length. Adjusting shock length longer will induce more front weight bias at the expense of swing arm angle numbers.
The taller you go the larger the angle, your ultimate working angle is approx 11-13'

Eg my 4xv is 305mm eye to eye, over 300mm standard. This puts my swing angle at 13' and feedback is great, the danger of +13' is the arm may try to fold under itself giving negative handling.
Many racebikes use fork extenders with tall rear shocks for varying reasons...

A taller shock will induce a faster turn in, not slower, if you put a shorter shock on you'd soon find the bike understeers, again I've learnt this first hand trying to learn how current gp technology is having bikes setup low at the rear, reasoning for this being to be able to utilise the extreme power they have!

24mm of rear sag is probably the tightest you'll want to go, the shock needs to work within a set range for optimum handling, one of the reasons we dial in a good base setting with sag. Too little sag and forks or shock can and may be induced to top out unnecessarily. This is one of the reasons behing top out springs, to help negate this, gets a lol complicated mind, lol.
 

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Aka longer eye to eye on shock ...Reducing weight bias on the rear to place it over the front, at the extreme this will induce a geometry tear on the rear tyre because of the tyre skipping over the tarmac and not being able to place the power down, akin to rebound being too fast.
 

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Magic numbers, let me pose this to you...Magic for who?

The hardest thing I encounter is with racers, they want to run somebody else's numbers.
A rider needs real honest evaluation here, what do they want, why do they want it and do they need it, once this is established then you can look at a plan of how to accomplish the mission.

I assume you race buddy? I only assume because I'm looking at your sag numbers and asking myself are you with those numbers because of soft springs and need extra preload or are your springs good and after testing you find your current setup needs the extra preload.

I don't advocate raising fork legs thru the yokes unless you really need too, this is only because of how Dave Moss schooled me! Especially if you have a shock which has adjustable length. Adjusting shock length longer will induce more front weight bias at the expense of swing arm angle numbers.
The taller you go the larger the angle, your ultimate working angle is approx 11-13'

Eg my 4xv is 305mm eye to eye, over 300mm standard. This puts my swing angle at 13' and feedback is great, the danger of +13' is the arm may try to fold under itself giving negative handling.
Many racebikes use fork extenders with tall rear shocks for varying reasons...

A taller shock will induce a faster turn in, not slower, if you put a shorter shock on you'd soon find the bike understeers, again I've learnt this first hand trying to learn how current gp technology is having bikes setup low at the rear, reasoning for this being to be able to utilise the extreme power they have!

24mm of rear sag is probably the tightest you'll want to go, the shock needs to work within a set range for optimum handling, one of the reasons we dial in a good base setting with sag. Too little sag and forks or shock can and may be induced to top out unnecessarily. This is one of the reasons behing top out springs, to help negate this, gets a lol complicated mind, lol.
I'll restate Magic to "jump off" numbers. I don't want to run anyone else's numbers I want to be able to put the bike where I want it while cornering. That means being able to feel the hell out of the front, IE ultimate confidence in what it's doing. I had an '05 GSXR setup by the previous owner and a local suspension shop hated the setup, guaranteeing they could make is so much better. It was way worse and I've been chasing the initial feeling ever since.

From what they said the front was overloaded and rear way up with a soft rear spring.

What's wrong with my current sag? Looks like the numbers most everyone is running. Front springs are 1.05 KG, I'm 190 lbs naked.

My rear shock is OE Length and I have a ride ht. adjustment rod +7mm from OE. I'll measure my angle today.
 

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Just confirm what bike we are talking about here buddy and what your problem is, your mission statement is just what it should be ;-) and you are looking for more front end feel.

Not dissing your sag numbers at all buddy, all depends upon where they started from, ideally on a 120mm travel fork 'racesag' wants to be 33% of total travel as a BASE line and with a shock that gives 120mm wheel travel approx 30mm race sag are good starting numbers...Checking static sag to see if the spring rate is close.

Your naked weight isnt much help, its rider weight with kit on that counts, if you give me your weight in gear that would help us more with a spring rate suggestion. Again these are suggestions, many racers will have a few sets of springs dependant upon differing factors. Re:- your shock spring rate, the most appropriate way is checking static sag unless you have data logging! (you ideally want approx 2-10mm for a non topout spring shock and approx 5-15mm for a shock which has a top out spring fitted).

Again style of riding, and other variables all come into account, but the spring rate calculators are fairly accurate and all based upon a similar equation and yet again, these are all only suggestions, ultimately its what inspires confidence and allows you to do what you want with the bike ;-)

is this a dog bone that is adjustable, they do not correlate the same way in adjustment as what shock length does, +7mm on a dog bone is not the same as +7mm on the shock, it also alters the geometry of the linkage and the progressiveness or not as the case may be of the linkage.

What are your specific symptoms, you say the front end feels vague with no feeling...
One thing to take into consideration is tyres are apart of the equation, tyre flex, pressures etc etc.

I could suggest that someone who states they have a lack off feel/vagueness in the front may want to try increasing the compression in the fork sso if you have the time and you are prepared to put some spanner time in there a couple of us on here who are more than willing to help and you could save some money, it really is better to write down your current settings and start from a good known baseline than trying to chase a problem away, this will have a twofold effect in that you have a set data for your baseline to work from and that you will learn more about your chassis than you may or may not know now ;-)
 

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A little more on 'dog bones' and linkage, alot of this info comes is sourced from Dave Moss, we had a discussion not so long ago about dog bone length's...

"The more you change the dog bone length, the more you shorten the shock. That is a general rule of thumb we all know works. Rider ability ensures that there's no equation that matches grip levels and the linear nature of the curve once the linkage is changed. Generally, if you change the linkage and dog bones, the manufacturer has a suggested starting point on shock length. From there you may need to respring and revalve based on something as simple as grip coefficient."

As you may or not know there are infinite methods of fine tuning a chassis setup, the interesting innovation coming slowly to the for-front is electronic adjustable suspension...however from talking with Dave the adjustment process is significantly more time consuming!
 

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Turn and Burn!
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Check in

Hey,

I haven't been back in a while, but I just wanted to thank everyone again for all their help! :icon_wink: My suspension issues have been a thing of the past and the bike is feeling great. I've gone through every tire manufacturer raceside (Dunlop, Pirelli and Bridgestone) and had to make minor adjustments here and there. Ii think I finally settled on Bridgestone. But all in all, things have been very good. Its good to know there are some really helpful, knowledgeable guys out there willing to help. My season is just about over and I should end up taking second place Amateur overall. Without your help, who knows where I'd be! Thanks!

Here's a recent pic from my last race! :fork
 

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Anyone able to help with an Ohlins Shock shim stack, or has access to ohlins database.

just got an Ohlins rear shock, stripped for service...

the stacks have been changed and unsure of the rebound bleed jet size, i have the spec card for the shock and the comp stack hugely differs.

Its got a 90n spring, used 85-90 on my wp comp shock. Based upon 75% fast road (not commuter)/25% track use, novice group. 99 race prepped R1so a few kg lighter than oem and my weight of 63kg in riding gear.

I can post the stack list if needed both oem and current.

Would like to know if stack is suitanle or should it be changed for me..???

Thanks in advance
 

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Crash OverRide
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What would be a good setting for street riding with me being 6'5" at 260 lbs? i mean besides me losing weight (lol) 2011 R1 with stock suspension forks and rear shock. Ive read this entire thread which will come in handy when I go to the track. Any thoughts on settings or opinions?
 
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