Need to improve my rear suspension - any recommendations, advice ?

[AnonymousGeorge]

Dear Riders, 

I have SW-Motech Pro side racks and panniers for quick mount/disassembly for soft luggage installation in case of off-road journey. With two side aluminium SW-Motech panniers and 1 galon rotopax, I am not able to set proper sag. My weight is around 90kg with full suite. During harder off-road (jumps etc.) my suspension is bottoming out. I am considering now an upgrade. Don't want to spent thousands euro for it but most guys recommends to change rear spring for more stiffer one. I don't want to lose excellent on-road bike capabilities. Would this change require front springs upgrade as well? Valving change? What sets do you recommend? 

By now, I am aware of touratech, rallyraid, hyperpro. Anything else?

[Tazmool]

First thing, measure your front and rear static sag.   (it sounds like you may have already done this) 

You mention you cannot set your static sag, is this front and rear?  or just rear? 
As far as I know, the rear spring on the T7 is undersprung (the rear spring is for 155lbs riders), but the front springs seem to be ok for most riders. 

If your front sag is ok, and rear is out. I would definitely go for a properly sized rear spring.  This is by far the easiest to do and a good place to start.  Having a stiffer spring in the back, and getting proper sag front and rear, will only improve the bike's handling in all conditions.

 

Rear spring.  Start there. 

 

If your front sag is not correct, you will have to swap out the front springs as well.  The T7 oddly does not have front preload adjustment, so once you get the proper springs in there, you may have to play with different length spacers as well.  

The fronts may be ok though, you could even start with a spacer in the front forks (if your sag is not correct) before swapping out springs.  Measure your static sag.

 

I'd also start with linear springs (non progressives, so that rules out HyperPro, at least for now)  

 

Tazmool

[loneranger700]

1 hour ago, Tazmool said:

First thing, measure your front and rear static sag.   (it sounds like you may have already done this) 

You mention you cannot set your static sag, is this front and rear?  or just rear? 
As far as I know, the rear spring on the T7 is undersprung (the rear spring is for 155lbs riders), but the front springs seem to be ok for most riders. 

If your front sag is ok, and rear is out. I would definitely go for a properly sized rear spring.  This is by far the easiest to do and a good place to start.  Having a stiffer spring in the back, and getting proper sag front and rear, will only improve the bike's handling in all conditions.

 

Rear spring.  Start there. 

 

If your front sag is not correct, you will have to swap out the front springs as well.  The T7 oddly does not have front preload adjustment, so once you get the proper springs in there, you may have to play with different length spacers as well.  

The fronts may be ok though, you could even start with a spacer in the front forks (if your sag is not correct) before swapping out springs.  Measure your static sag.

 

I'd also start with linear springs (non progressives, so that rules out HyperPro, at least for now)  

 

Tazmool

Hey tangentially related, but how do we measure the front sag? Like, I'm not sure if it was adjusted from factory or not, so I'm kind of afraid to even touch it in fear that I would actually be pushing it farther out from the wrong direction if it wasn't actually set to "normal".

Edited August 7, 2020 by loneranger700

[Goldentaco]

12 minutes ago, loneranger700 said:

Hey tangentially related, but how do we measure the front sag? Like, I'm not sure if it was adjusted from factory or not, so I'm kind of afraid to even touch it in fear that I would actually be pushing it farther out from the wrong direction if it wasn't actually set to "normal".

Jump on bike, bounce suspension back and forth.  Get off, put a zip tie on a fork leg or both just tight enough so it stays in place.  Hop on bike, don't bounce it, sit with all your weight on it.  Then get off have some one help you lift up on the front to remove all weight and measure how far down the zip tie is from the upper dust seal.  = Front sag.  

 

J

[TimmyTheHog]

1 minute ago, loneranger700 said:

Hey tangentially related, but how do we measure the front sag? Like, I'm not sure if it was adjusted from factory or not, so I'm kind of afraid to even touch it in fear that I would actually be pushing it farther out from the wrong direction.

front? This is how I was taught.

To Start, I lift up the front end of the bike and let it dangle, then I measure the exposed chrome tube length as my fully extended (X)

 

Let the bike sit back on the ground w/o rider, measure the same chrome tube (Y). The difference of that will be static sag (X -Y = A)

 

then sit on the bike with all your gear/luggage if needed, have a 2nd person measures the shorten chrome tube length (z).

 

If you don't have a 2nd person with you, you can tie a zip tie to the chrome tube and push against the fork outer tube before you sit on the bike. Once you sit on the bike, the fork outer tube will push the zip tie down to some point. Measure the zip tie to the bottom end of the chrome tube (Z). The new difference between (Z) and (X) will be your Rider sag (B)...

 

To those who are more experienced, if I am doing this wrong, please correct me.

 

[loneranger700]

Wait, so this is how I can figure out how far in or out my forks have been adjusted from factory?

Edited August 7, 2020 by loneranger700

[Goldentaco]

39 minutes ago, loneranger700 said:

Wait, so this is how I can figure out how far in or out my forks have been adjusted from factory?

It will tell you whether your front spring is stiff enough and or needs more preload.

 

For comparison my Front Race Sag is 70 and Rear is also 70.  Ideally it should be 60 on both ( 200m total X 30%).  On the front I would need to add spacers for more preload probably 5mm at a time.

 

Rear I'm at 13clicks out from full preload so even though I can get my numbers there I shouldn't have to use all my adjustability to make that so I would definitely add a stiffer spring there.  Most likely I would respring both. I weight 220 in street clothes and 240 in full gear.

 

J

 

 

Edited August 7, 2020 by Goldentaco

[Tazmool]

All good points above, and a quick vid summing it up:

 

How To Check Motorcycle Suspension Sag | MC Garage

 

Remember, on the T7, the front preload is not adjustable

(automatically making the T7 suspension NOT-Fully Adjustable, despite what anyone claims) 

To adjust the front preload you will need to install different length spacers in the forks, install preload adjustable fork caps etc.  Or replace the front springs (if needed)  chances are that you won't have to do much if anything to the front.

 

Tazmool

[AnonymousGeorge]

3 hours ago, Tazmool said:

First thing, measure your front and rear static sag.   (it sounds like you may have already done this) 

You mention you cannot set your static sag, is this front and rear?  or just rear? 
As far as I know, the rear spring on the T7 is undersprung (the rear spring is for 155lbs riders), but the front springs seem to be ok for most riders. 

If your front sag is ok, and rear is out. I would definitely go for a properly sized rear spring.  This is by far the easiest to do and a good place to start.  Having a stiffer spring in the back, and getting proper sag front and rear, will only improve the bike's handling in all conditions.

 

Rear spring.  Start there. 

 

If your front sag is not correct, you will have to swap out the front springs as well.  The T7 oddly does not have front preload adjustment, so once you get the proper springs in there, you may have to play with different length spacers as well.  

The fronts may be ok though, you could even start with a spacer in the front forks (if your sag is not correct) before swapping out springs.  Measure your static sag.

 

I'd also start with linear springs (non progressives, so that rules out HyperPro, at least for now)  

 

Tazmool

I did checked the static sag with fully loaded bike and my rear suspension seats definitely too low. There is also some extra weight put on top of bike: crash-bars, side+main rack, toolbox (around 12.5 kg)

 

Why should I avoid progressive springs ? (Hyperpro) Can you please explain this further?

 

Any possibility to modify front OEM suspension to implement adjustable preload ? 

-----Edit-------
Ok, you answered to my last question already. I would be interested in adding adjustable fork caps. Any suggestion where to order these? 
 

Edited August 7, 2020 by AnonymousGeorge

[TimmyTheHog]

44 minutes ago, AnonymousGeorge said:

I did checked the static sag with fully loaded bike and my rear suspension seats definitely too low. There is also some extra weight put on top of bike: crash-bars, side+main rack, toolbox (around 12.5 kg)

 

Why should I avoid progressive springs ? (Hyperpro) Can you please explain this further?

 

Any possibility to modify front OEM suspension to implement adjustable preload ? 

-----Edit-------
Ok, you answered to my last question already. I would be interested in adding adjustable fork caps. Any suggestion where to order these? 
 

Not sure about other company especially in North America, but Rally Raid makes them

 

Yamaha T7 Fork Preload Caps-RRP 614

 

[Tazmool]

Progressive springs do serve a purpose, but they are a comprimise in the sense that the valving/damping of the suspension is not meant to be variable according to the stroke position of the shock (meaning the damping is the same no matter where in the stroke travel the suspension is)  so if you use a progressive spring, the damping may be ideal in the middle of the spring travel but not at the bottom or top of the travel range. 

 

This is why a linear spring is preferrable, you get controlled damping throughout the entire range of the suspension travel.  If the shock linkage is slightly progressive, that gives it some anti bottoming out properties.

 

Progressive springs are great if the suspension has to deal with a very large range of weight, and or a wide range of conditions where you are trying to avoid bottoming out but want a lighter spring towards the static sag end.

 

There is nothing wrong with HyperPro progressive springs, I've used them myself in my past bikes with good results.  
However, if you are going to replace just the rear spring, you're better off going with a oem style, non progressive spring, just one made for the weight range you are after. 

 

As for adjustable preload front fork caps, 
I would honestly first measure your sag, if its good, or close, you're much better off making a spacer that will get you into the right sag range.  Usually front preload changes are not necessary once they're set.  Most of the weight change is in the rear (luggage, passenger etc) and thats why rear preload is almost always adjustable, while front is not.   Also, once you get the sag right, you almost never have to change the settings. 

 

Tazmool

[Camel ADV]

Be aware that when the forks are fully compressed on the T7, that there's 30mm of shaft still showing so make sure you're doing your math with that factored in. You'll have 230mm of shaft visible at full extension. 30% of 230mm = 69mm sag but you're actually a looking for 30% of 200mm (60mm).

[AnonymousGeorge]

Thank you guys. I will start with new rear spring + front sag check and potential spacers. These preload adjustable caps seems to be way too expensive. Will get back to you with my calculations.
  

[Vtamb81]

On 8/8/2020 at 6:40 AM, AnonymousGeorge said:

Thank you guys. I will start with new rear spring + front sag check and potential spacers. These preload adjustable caps seems to be way too expensive. Will get back to you with my calculations.
  

Great information everyone. I feel like I’m a pretty smart guy, but sometimes suspension work makes me cross eyed!

 

I’m planning on the exact same thing. RR just released some cheap front fork preload spacers that I’m going to use with the stock front fork caps. I’ll throw them in the cart with a new rear spring and start there. 

[Ktmmitch]

On 8/7/2020 at 8:16 PM, Tazmool said:

All good points above, and a quick vid summing it up:

 

How To Check Motorcycle Suspension Sag | MC Garage

 

Remember, on the T7, the front preload is not adjustable

(automatically making the T7 suspension NOT-Fully Adjustable, despite what anyone claims) 

To adjust the front preload you will need to install different length spacers in the forks, install preload adjustable fork caps etc.  Or replace the front springs (if needed)  chances are that you won't have to do much if anything to the front.

 

Tazmool

Yamaha T7 Fork Preload Washers-RRP 628

 

[AnonymousGeorge]

On 8/12/2020 at 5:48 PM, Vtamb81 said:

Great information everyone. I feel like I’m a pretty smart guy, but sometimes suspension work makes me cross eyed!

 

I’m planning on the exact same thing. RR just released some cheap front fork preload spacers that I’m going to use with the stock front fork caps. I’ll throw them in the cart with a new rear spring and start there. 

Get back to us with your findings and feelings

 

[MGG]

On 8/8/2020 at 3:23 AM, Camel ADV said:

Be aware that when the forks are fully compressed on the T7, that there's 30mm of shaft still showing so make sure you're doing your math with that factored in. You'll have 230mm of shaft visible at full extension. 30% of 230mm = 69mm sag but you're actually a looking for 30% of 200mm (60mm).

is that 30mm from the bottom of the tube to the bottom of the dust seal ?

 

Also ... I think that the front fork have 210mm of travel ... the rear is 200mm 

so the front 30% would be 66mm 

[Camel ADV]

7 minutes ago, MGG said:

is that 30mm from the bottom of the tube to the bottom of the dust seal ?

 

Also ... I think that the front fork have 210mm of travel ... the rear is 200mm 

so the front 30% would be 66mm 

Bottom of the dust seal. I have seen 210mm listed as the front travel but actual measured was 200mm. There is a top out spring in the rod though so perhaps, they are counting that as travel too... IDK.

[Ktmmitch]

Correct Cory, with the forks stripped and spring removed I measured 202mm of travel, so I suppose Yamaha decided to add the stroke of the top-out spring for good measure......a bit of creative accounting (or marketing)

[Noel McCutcheon]

On 8/7/2020 at 4:21 PM, AnonymousGeorge said:

Dear Riders, 

I have SW-Motech Pro side racks and panniers for quick mount/disassembly for soft luggage installation in case of off-road journey. With two side aluminium SW-Motech panniers and 1 galon rotopax, I am not able to set proper sag. My weight is around 90kg with full suite. During harder off-road (jumps etc.) my suspension is bottoming out. I am considering now an upgrade. Don't want to spent thousands euro for it but most guys recommends to change rear spring for more stiffer one. I don't want to lose excellent on-road bike capabilities. Would this change require front springs upgrade as well? Valving change? What sets do you recommend? 

By now, I am aware of touratech, rallyraid, hyperpro. Anything else?

For Rear ........ if you and luggage weigh over 200 lbs upgrade spring. 90 nm for 220 lbs 98kg rider. 

[AnonymousGeorge]

On 10/14/2020 at 6:19 PM, X Plane said:

For Rear ........ if you and luggage weigh over 200 lbs upgrade spring. 90 nm for 220 lbs 98kg rider. 

Not sure if I got you.

Do you mean 90Nm REAR spring for 200lbs rider (aprox 98kg weight)? 

[Noel McCutcheon]

On 10/19/2020 at 3:35 PM, AnonymousGeorge said:

Not sure if I got you.

Do you mean 90Nm REAR spring for 200lbs rider (aprox 98kg weight)? 

Correct. Yes, a 100 kg rider would need the 90Nm spring.
A 130kg rider would need 95Nm spring

[AnonymousGeorge]

I checked my weight and I am 88kg in full gear. Which one should I go for?80, 85 or 90Nm?

[Uncle M]

@AnonymousGeorge, here is the list from Rally Raid's website: You could email them to confirm whether 85 or 90, depending on how much luggage you're going to carry.

 

Select the appropriate spring, from the drop-down menu above, based on rider, passenger & luggage loads below:

Rider(up to 75kg, inc clothing) with max 50kg luggage.................................................80N/mm

Rider(up to 85kg, inc clothing) with max 50kg luggage.................................................85N/mm

Rider(up to 95kg, inc clothing) with light passenger and/or 15kg luggage..................90N/mm

Rider(up to 105kg, inc clothing) with passenger and/or 30kg luggage.........................95N/mm

[JayD]

I just fitted a heavier spring from Rally Raid. Im not the most experienced rider, so I didnt really know what to expect.

 

But let me say, the bike felt like a completely new bike, in a good way. Im not sure if this is correct, but with the heavier spring I had less sag, which made the rake narrower. The front wheel felt closer to me than before, and the handling was therefore much crisper.

 

Im amazed how much better the bike felt and handles from a 80$ spring. Now, lets fix the front 

 

Johannes.