suspension Settings Advice

[betoney]

41 minutes ago, mike said:

You seem to think that setting the rebound on maximum will literally stop all movement in the forks and shock. If you think about it, Yamaha has designed the rebound circuit to work in a range they feel comfortable allowing a rider to use. If they designed a system that would not allow sufficient movement when set to the max or gave no resistance when set to the minimum, the layers would be lining up for a piece of the pie. The shock and the forks have max and min settings that can be used or that range of adjustment would not built into the design.

For someone my weight, the shock and forks move quite a bit in compression when riding and the slower rebound prevents the pogo effect. When custom suspensions are set up one thing that is often added, as I understand it, is more dampening in the rebound circuit. As long as the rebound does not cause the spring to pack up and will allow the spring to unload before the next compression, all is good.

@mike  when you said - "As long as the rebound does not cause the spring to pack up and will allow the spring to unload before the next compression, all is good."  - I cant imagine that the shock or forks could react fast enough to respond effectively for the next bump.  Though my experience is with aftermarket suspension where one or two clicks makes a very noticeable difference and if you have either compression or rebound damping close to being maxed out the reaction is VERY slow and depending on the road surface, could be extremely harsh.

If the suspension seems to work for you with those settings, then you have lucked out.  👍😎

 

[mike]

2 hours ago, wordsmith said:

As a skinny bugger I mean no disrespect here - but aren't some of you 250lb-plus guys expecting too much from a bike of this size and weight and just plain ornery suspension ex-factory?

No disrespect taken. As I stated, I have no problem with the stock suspension. It works just fine for me and my ability. I am not babying the bike and am using most of the tire.

[mike]

1 hour ago, betoney said:

I cant imagine that the shock or forks could react fast enough to respond effectively for the next bump. 

If the shock would not work at the settings supplied, why in the world would Yamaha give you the option?

[StealthAu]

11 minutes ago, mike said:

If the shock would not work at the settings supplied, why in the world would Yamaha give you the option?

Go over some carpark speed bumps at 10kmph. 

Your wheels would leave the ground, the bike will buck. 

Being in the available adjustment range doesn't mean it isn't over dampening at that point. 

Stand your bike up, push down on the seat and watch it rise up. 

It needs to be able to react in a manner so that when you go over bumps, after the springs compress, they extend fast enough to maintain contact with the ground. Stock gt suspension with that much rebound damping moves way too slow.

[StealthAu]

3 hours ago, wordsmith said:

As a skinny bugger I mean no disrespect here - but aren't some of you 250lb-plus guys expecting too much from a bike of this size and weight and just plain ornery suspension ex-factory?

Yes. I'm only 220lbs and every bike I have owned required heavier springs as a minimum. 

You can make the suspension work as best it can in stock form, but having it sprung to your weight makes a world of difference. 

 

[mike]

OK, This may be my last post on this issue. 

"Sp0okz" appears to be a fairly new rider asking for advice setting up the "stock" suspension for someone around his weight. I answered with the settings that have worked for me after adjusting over the last 5,000 miles or so. I am not an expert rider but I ride fairly rough roads at a pace that the Chicken Strips on my tires are fairly narrow. I have a feeling that he is not going to run out and install $1,000 in improvements to his suspension at this stage of the game. He may very well find that he pushes the bike hard enough in the future that those improvements are needed. After a test at these settings , it would be pretty easy to return to the stock settings and start over if that is desired.

I have ridden the bike with these rebound adjustments and found them to work. Anyone who thinks I am delusional might want to set things up the way I have and test ride a bike with "stock" suspension and give it a try. I do understand that anyone much lighter than me will probably find things too harsh but I don't think they will find the bike unrideable.  

Once again I am not dragging a knee and don't ride with a lot of extra weight on the bike for trips or camping. I am sure there are many things I could do to make the bike handle better but it suits my purpose just fine the way it is. That may change in the future but only time will tell.

[StealthAu]

1 hour ago, mike said:

OK, This may be my last post on this issue. 

"Sp0okz" appears to be a fairly new rider asking for advice setting up the "stock" suspension for someone around his weight. I answered with the settings that have worked for me after adjusting over the last 5,000 miles or so. I am not an expert rider but I ride fairly rough roads at a pace that the Chicken Strips on my tires are fairly narrow. I have a feeling that he is not going to run out and install $1,000 in improvements to his suspension at this stage of the game. He may very well find that he pushes the bike hard enough in the future that those improvements are needed. After a test at these settings , it would be pretty easy to return to the stock settings and start over if that is desired.

I have ridden the bike with these rebound adjustments and found them to work. Anyone who thinks I am delusional might want to set things up the way I have and test ride a bike with "stock" suspension and give it a try. I do understand that anyone much lighter than me will probably find things too harsh but I don't think they will find the bike unrideable.  

Once again I am not dragging a knee and don't ride with a lot of extra weight on the bike for trips or camping. I am sure there are many things I could do to make the bike handle better but it suits my purpose just fine the way it is. That may change in the future but only time will tell.

Mate, don't take it personally or feel like you need to defend yourself. 

 

I understand why you would feel a need to max out rebound damping.

Under braking, you don't have enough front spring. Compresses hard and fast. High rebound in the rear slows the weight transfer. 

You don't have enough spring in the rear, so you crank up the rebound damping in the front to limit squat under acceleration. 

 

The downside of taking this approach is when going over bumps, your wheels can't return from the compression cycle fast enough to maintain contact with the road. 

 

You can increase front compression to reduce fork dive which in turn, will allow you to reduce rebound in the rear. This will be an improvement to your current settings. 

 

For upgrades, all you really need are new springs front and rear and a heavier fork oil. For this, you'd only be looking at a couple hundred dollars. 

 

[sp0okz]

I got mine all setup from a guy in the North East of England its what he does and he also races the TT so hes good at what he does.

Bike is now handling alot better only problem i have now is front end over 100mph starts tank slapping slowly....

[dmanteigas]

On 6/28/2019 at 11:30 PM, StealthAu said:

I checked the part number for the gt fork springs, 0.75kg/mm fixed rate.

Are you sure? Can you send me the reference? Because according to info I have, it's progressive 7.5-10

[StealthAu]

5 hours ago, dmanteigas said:

Are you sure? Can you send me the reference? Because according to info I have, it's progressive 7.5-10

What info have you got?

[dmanteigas]

11 hours ago, StealthAu said:

What info have you got?

https://www.carpimoto.com/EN/42720_Matris-Fork-Springs-Kit-for-Yamaha-Tracer-900-18-.htm

[StealthAu]

 

17 minutes ago, dmanteigas said:

https://www.carpimoto.com/EN/42720_Matris-Fork-Springs-Kit-for-Yamaha-Tracer-900-18-.htm

 

Interesting.

I went here and got the part number of the Tracer GT stock springs.

2019 Yamaha TRACER 900 GT (MTT9GTKB) Front Fork | Babbitts Yamaha Partshouse

---

Shop online for OEM Front Fork parts that fit your 2019 Yamaha TRACER...

I  then checked what other models use the same springs, partzilla is good for this. Same part number for springs in all tracers/fj09's since 2015.

Racetech and other sources I could find indicated a constant rate spring. 

I said 0.75kg/mm before, that was actually the mt09. Tracers get 0.70kg/mm.

 

[captainscarlet]

On 6/24/2019 at 6:42 PM, sp0okz said:

Hey All,

I passed my test around a month ago and jumped into the deep end and got a Multistrada but it was a bit much for me so i traded it for  tracer 900 GT im a chunky monkey and the suspention seems to be very soft as on the ducati it auto ajusted it's self and i dont know too much about the ajustments yet on bikes.

Im 252lbs i feel when i back off the throttle i slide forward or when breaking also front end seems very soft and also i feel like im getting bounced all over on normal roads with few bumps in them

any help i will be good thanks

Before doing anything else you want to set the rider sag.  This means adjusting the preload at the front and back so that approximately 30% of the available suspension travel is used up with you sitting on the bike in your normal riding gear.  On the GT this means roughly 41 mm of travel front and back.

What you do is lift the front of the bike so the wheel is off the ground and measure the exposed tube at the bottom of the fork leg.  Then get on the bike, feet on the pegs and steadying yourself against a wall or similar get a nearby assistant to take the same measurement.  The difference between the unloaded and loaded measurement is your rider sag and as mentioned you're looking for around 41 mm.  Do the same at the rear.  Put the bike on the centre stand and from the axle measure to a fixed point on the bodywork directly above the rear axle.  Get on the bike again and ask your assistant to take the same measurement again.

If you have less than 41 mm then you need to reduce preload, which in turn means that if you have more than 41 mm rider sag you need to add preload.

Once you've got your preload dialed in you can start fiddling with rebound.  Here you are looking for the suspension to quickly and smoothly, without bouncing up and down, return to it's rest position having been compressed.  You can test this in the garage by pushing firmly down and then releasing the handlebars to compress the front forks.  At the rear simply push down firmly on the rear seat and release.

I made 3 videos to demonstrate what you're looking for in terms of rebound, which you can find here:

Once you've got rebound dialed in in the garage you can fine tune it on some of your favourite roads.

CS

 

[StealthAu]

On 7/2/2019 at 6:57 PM, dmanteigas said:

https://www.carpimoto.com/EN/42720_Matris-Fork-Springs-Kit-for-Yamaha-Tracer-900-18-.htm

Just letting you know, your info was right, mine was wrong. 

I just swapped out the stock springs and yes, they are progressive.