Rear sag with lowering link

[Insane rider]

Hi all,

 

I was looking at the rally raid website and they are saying the -20mm lowering link will reduce the rear wheel travel by the same amount 

Yamaha T7 Lowering Links 20mm-RRP 637

 

My question is, to have the 30% rider sag with the lowering link, do I use 30% of 200mm (60mm) or 30% of 180mm (54mm)? 

[qInvention]

The sag is always calculated on the basis of available travel. So you want to set sag on 30% of 180mm.

[Murska]

The lowering link does not shorten the suspension travel, although the link lowers the bike by 20mm, but the suspension travel remains at 200mm.

[Landshark]

3 hours ago, Murska said:

The lowering link does not shorten the suspension travel, although the link lowers the bike by 20mm, but the suspension travel remains at 200mm.

 

I've replaced mine to 20mm and yes you must deduct that from your travel and yes that would be 180mm   

There are good vids out on how to accomplish this.

I used this one 

 

[Insane rider]

I’m reading mixing opinions on this

I did more research on it after writing it here and looks like it doesn’t reduce travel.

 

Not sure why Rally Raid are saying this.

maybe the geometry of the T7 actually reduce the travel with a link.

 

To me it only change the height of the wheel and not reducing travel like a internal modification of the shock.

 

[Landshark]

3 hours ago, Insane rider said:

I’m reading mixing opinions on this

I did more research on it after writing it here and looks like it doesn’t reduce travel.

 

Not sure why Rally Raid are saying this.

maybe the geometry of the T7 actually reduce the travel with a link.

 

To me it only change the height of the wheel and not reducing travel like a internal modification of the shock.

 

 

When you go to set your sag, you'll find you can't achieve it unless you factor in the 20 mm.  I found that the preload on the rear shock needs to be cranked to the nines to have success.  When you factor the 20 mm into the equation it works perfectly.  Try it, you'll like it.

[Quercus Petraea]

1 hour ago, Landshark said:

 

When you go to set your sag, you'll find you can't achieve it unless you factor in the 20 mm.  I found that the preload on the rear shock needs to be cranked to the nines to have success.  When you factor the 20 mm into the equation it works perfectly.  Try it, you'll like it.

I don’t think that is because travel is affected (it’s not).

Is just the progressiveness what is affected, and once you put lowering links, you should put a stiffer spring too.

 

May be Mitch from Rally Raid can lighten us a little more

Edited July 9, 2021 by Quercus Petraea

[Insane rider]

The more  i read on this the more I’m sure it doesn’t affect traveling 

i was easily able to adjust 60mm sag with a 90 N/mm spring

[Alan M]

1 hour ago, Quercus Petraea said:

I don’t think that is because travel is affected (it’s not).

Is just the progressiveness what is affected, and once you put lowering links, you should put a stiffer spring too.

 

May be Mitch from Rally Raid can lighten us a little more

Agreed, I was thinking it just lowers the position of the shock. To reduce travel you would have to change the shock internals.

 

A bit like dropping the forks through the clamps, travel is the same but the bike is now lower to the ground.

 

The payback to these two mods is a change in suspension geometry which might change it in a slightly negative way.

[Insane rider]

2 hours ago, Alan M said:

Agreed, I was thinking it just lowers the position of the shock. To reduce travel you would have to change the shock internals.

 

A bit like dropping the forks through the clamps, travel is the same but the bike is now lower to the ground.

 

The payback to these two mods is a change in suspension geometry which might change it in a slightly negative way.

And that’s the reason suspensions specialist don’t like lowering link.

Because if you lower too much with a link it’s possible the wheel will touch the fender and it’s dangerous 

 

[Quercus Petraea]

19 minutes ago, Insane rider said:

And that’s the reason suspensions specialist don’t like lowering link.

Because if you lower too much with a link it’s possible the wheel will touch the fender and it’s dangerous 

 

That’s a risk, but the Tenere still has about a 15 or 20 mm margin if you put lowering links.

[Goldentaco]

16 minutes ago, Insane rider said:

And that’s the reason suspensions specialist don’t like lowering link.

Because if you lower too much with a link it’s possible the wheel will touch the fender and it’s dangerous 

 

Rally Raid is right.  Travel is affected but as you figured, it's the wheel possibly contacting the fender being the limiting factor not some shock stroke issue.

 

Also on rear suspensions with a progressive link, elongating the link lowers the bike physically.  It also increases the leverage the wheel has in order to move the shock.  This effectively reduces the spring rating.

 

ON this bike, the progressive linkage is noticeable with stock spring for heavier riders as it's a harsher ride.

 

If you lower with a stock spring it like the worst of worst.

 

I'm not sure what length of linkage would relate to an increased spring rating.  You stated you have a 90 nm spring and were able to set sag so you should be ok.

 

As for compensating for he linkage setting sag, I doubt you'd notice the difference between 6mm in ride height.  20mm or more probably.

 

J

[Quercus Petraea]

11 minutes ago, Goldentaco said:

Rally Raid is right.  Travel is affected but as you figured, it's the wheel possibly contacting the fender being the limiting factor not some shock stroke issue.

 

Also on rear suspensions with a progressive link, elongating the link lowers the bike physically.  It also increases the leverage the wheel has in order to move the shock.  This effectively reduces the spring rating.

 

ON this bike, the progressive linkage is noticeable with stock spring for heavier riders as it's a harsher ride.

 

If you lower with a stock spring it like the worst of worst.

 

I'm not sure what length of linkage would relate to an increased spring rating.  You stated you have a 90 nm spring and were able to set sag so you should be ok.

 

As for compensating for he linkage setting sag, I doubt you'd notice the difference between 6mm in ride height.  20mm or more probably.

 

J

But there’s a contradiction there.

 

If you put -20mm lowering links and the travel is affected by that same amount, then the tyre could never touch the rear fender, as it should stop at the very same point as you never put the lowering links.

 

That risk only could exist if the travel is NOT affected, right? Or am I missing something?

[Insane rider]

7 minutes ago, Quercus Petraea said:

But there’s a contradiction there.

 

If you put -20mm lowering links and the travel is affected by that same amount, then the tyre could never touch the rear fender, as it should stop at the very same point as you never put the lowering links.

 

That risk only could exist if the travel is NOT affected, right? Or am I missing something?

A lowering link doesn’t affect travel.

plain and simple

 

[Goldentaco]

47 minutes ago, Quercus Petraea said:

But there’s a contradiction there.

 

If you put -20mm lowering links and the travel is affected by that same amount, then the tyre could never touch the rear fender, as it should stop at the very same point as you never put the lowering links.

 

That risk only could exist if the travel is NOT affected, right? Or am I missing something?

No

Links don’t always limit travel but they can if they’re too long. 

20 mm isn’t too low that it will hit. RallRaid also sells a 40 mm too. That might hit. More than that and you will have problems. Every bike has a different margin here to work with. 
 

-20mm links reduce your available under fender clearance by 20 mm all before your shock even compresses. Add a -60mm link same thing. Regardless of what the shock is capable of lowering links set the wheel closer to the bodywork. 

Try this, remove one of the link bolts so you can swing rear swing arm up to hit the fender. Now hold it there.  You’ve just added a lowering link. Shock hasn’t compressed but you’ve reduced your rear wheel available travel. 
 

J

Edited July 9, 2021 by Goldentaco

[Quercus Petraea]

5 hours ago, Goldentaco said:

No

Links don’t always limit travel but they can if they’re too long. 

20 mm isn’t too low that it will hit. RallRaid also sells a 40 mm too. That might hit. More than that and you will have problems. Every bike has a different margin here to work with. 
 

-20mm links reduce your available under fender clearance by 20 mm all before your shock even compresses. Add a -60mm link same thing. Regardless of what the shock is capable of lowering links set the wheel closer to the bodywork. 

Try this, remove one of the link bolts so you can swing rear swing arm up to hit the fender. Now hold it there.  You’ve just added a lowering link. Shock hasn’t compressed but you’ve reduced your rear wheel available travel. 
 

J

Ok, agree. That’s what i thought.

So, when somebody says that lowering links reduce suspension travel is just talking about a posible limitation due to the avaiable “gap” between the wheel and the body work, so the wheel could reach the body work before the shock gets full conpressed.

But regardless of the body work/rear fender, travel shouldn’t be affected… am i right?

[Goldentaco]

1 hour ago, Quercus Petraea said:

Ok, agree. That’s what i thought.

So, when somebody says that lowering links reduce suspension travel is just talking about a posible limitation due to the avaiable “gap” between the wheel and the body work, so the wheel could reach the body work before the shock gets full conpressed.

But regardless of the body work/rear fender, travel shouldn’t be affected… am i right?

It comes down to semantics.  The discussion should separate Wheel travel from Shock travel.

 

So in this case a link doesn't directly affect shock travel.  A link directly affects or can affect/ wheel travel.

 

J

[jeff936]

Mitch (Rallyraid) wouldn't sell a product that would damage the bike, that wouldn't be good for business.

 

The T7 comes with 210m of travel on the rear (standard), and will still have 210mm of "travel" on the rear if 20mm lower links are installed.

From what I have read, "Travel" doesn't change unless a longer/shorter shock is installed or the back wheel hits the fender (bottoms out), not allowing the shock to reach full travel.

 

An example of this is Rally raids 230mm extreme rear shock. Travel has now changed.

 

As GoldenTaco said above, place the bike on a stand with the wheel just touching the ground, remove the bolt on the swing arm where the links connect. 

Then measure the distance the rear wheel travels up to the rear fender.

 

As an example (Not actual T7 numbers)

•           Wheel travels 240mm before hitting rear fender. (bottoming out)
•           Subtract 20 mm (lowering link) from 240mm (original full travel)
•           That gives 220mm of "clearance" before the wheel hits fender. (Bottoms out)
•           T7 suspension has 210mm of travel, leaving 10mm clearance. 

The shock itself only moves about 80mm, the linkage is what create the extra "travel"

 

One other thing to consider is tyre height, I know my Motoz traction 140 (I believe) has an extra 8mm on the stock tyre. 

Which would be close to bottoming out in the  example above. 

   

 The progressiveness of the linkage ratio will change with lowering links, i.e The suspension will be harder in the initial part of the stock because of the ratio change.

 

But someone way smarter than me will need to explain linkage ratios and what they do.   

 

Hopefully Mitch can enlighten us all on what that change is and the effect on the rear shock.           

 

 

[Quercus Petraea]

1 hour ago, jeff936 said:

Mitch (Rallyraid) wouldn't sell a product that would damage the bike, that wouldn't be good for business.

 

The T7 comes with 210m of travel on the rear (standard), and will still have 210mm of "travel" on the rear if 20mm lower links are installed.

From what I have read, "Travel" doesn't change unless a longer/shorter shock is installed or the back wheel hits the fender (bottoms out), not allowing the shock to reach full travel.

 

An example of this is Rally raids 230mm extreme rear shock. Travel has now changed.

 

As GoldenTaco said above, place the bike on a stand with the wheel just touching the ground, remove the bolt on the swing arm where the links connect. 

Then measure the distance the rear wheel travels up to the rear fender.

 

As an example (Not actual T7 numbers)

•           Wheel travels 240mm before hitting rear fender. (bottoming out)
•           Subtract 20 mm (lowering link) from 240mm (original full travel)
•           That gives 220mm of "clearance" before the wheel hits fender. (Bottoms out)
•           T7 suspension has 210mm of travel, leaving 10mm clearance. 

The shock itself only moves about 80mm, the linkage is what create the extra "travel"

 

One other thing to consider is tyre height, I know my Motoz traction 140 (I believe) has an extra 8mm on the stock tyre. 

Which would be close to bottoming out in the  example above. 

   

 The progressiveness of the linkage ratio will change with lowering links, i.e The suspension will be harder in the initial part of the stock because of the ratio change.

 

But someone way smarter than me will need to explain linkage ratios and what they do.   

 

Hopefully Mitch can enlighten us all on what that change is and the effect on the rear shock.           

 

 

Thanks.

 

Yes, I think we were talking the same from the begining, but the confussion came from thinking “travel” as a mathemathical result or as ditance between wheel and fender.

 

Just to be accurate: if my memory is still ok, T7 rear travel is 200mm (not 210) and shock stroke is 100mm (not 80), so the ratio is 2/1.

 

210mm travel is supossed to be the fork travel (is what Yamaha says), but it’s actually 200mm also.

Edited July 10, 2021 by Quercus Petraea

[jeff936]

Yes, sorry Quercus that's correct, I get lost in all the numbers, 210 up front and 200 rear, and 100mm shock.