Fork maintenance?

tntmo

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Joined
Nov 10, 2017
Messages
656
Location
San Diego, CA
I checked pricing from two suspension shops I have used in the past and they were both around $210-240 for complete service not including parts.(Canadian dollars) But this is you taking forks off bike. If I was going to pay someone I would send my stuff to a reputable suspension shop not a dealer. Preferably a shop who's primary work is on road race bikes. They will be quicker and you will know they are doing a full strip and refresh for a better price than a dealer who is likely just doing a dump and fill. Nothing wrong with a dump and fill, but I don't expect to pay the same as a full service.
Great write up. I will be replacing my fork seals (weeping/leakage from riding in mud) and will probably make a video of it as well.

If you are capable of putting your bike on the center stand and know how to remove the front wheel, you are officially competent enough to remove the forks and drain the fluid. I highly recommend it!
 

Various

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Joined
May 21, 2018
Messages
38
Location
UK
Prompted by the posts on here, I changed my fork oil last week. 36k miles. Drained out 585ml of fairly clean oil from the right hand leg and 485ml of old (olive green) oil from the left. Replaced it with 485ml of 5w in each leg. Presumably the previous owner did something to the right hand leg only and was a bit too enthusiastic when pouring the oil in. Maybe that's why the front has always felt harsh.

I removed the springs to check things over, but there was nothing much to see (hardly any debris in the bottom of the fork leg) so I wouldn't bother again. Mind you, having the top off made it easier to check and set the air gap above the oil (150mm).
 

Bombadier36

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Aug 8, 2019
Messages
81
Location
Florida Panhandle
Oof! Haven’t done mine yet and at 32,000 miles. It is on the top of my list now along with some other items that are due. Going to order a shop manual too and spend a couple weekends knocking some stuff out.

Thank you for all of the information.
 

TenereGUY

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Jan 19, 2023
Messages
1,011
Location
Illinois
Oof! Haven’t done mine yet and at 32,000 miles. It is on the top of my list now along with some other items that are due. Going to order a shop manual too and spend a couple weekends knocking some stuff out.

Thank you for all of the information.
Good, you'll be amazed at how stinky and muddy looking that oil will be and how much better the front end will be.
As stated in this thread... many people don't ever change their fork oil out and they should. Also said... how come it looks like that in a sealed system?
If you put a GoPro on your bike so it looks at the forks while running down the road you'll be amazed at the amount of times that forks actually cycle up and down even on what you think is a fairly smooth road. The forks are taking mechanical/kinetic energy and changing it into heat energy. So your fork oil heats up and then when the bike sits it cools down. Fork Seals are not perfect and a small amount of moisture does penetrate and that mixes in with the oil too. A lot of the blackness in the oil is the Teflon coating on the fork bushings wearing off the bushings through friction. It's designed to do that as the Teflon is the sacrificial coating. You want that to wear instead of the forks aluminum tube. If you keep riding and don't service your forks the Teflon wear is accelerated and then the inside of the fork tube starts to wear and that causes problems. Your fork tube wears as it is softer than the steel bushing. I know Honda says to change the bushings if 3/4 of the Teflon is gone. (My 1st Yamaha and I haven't read in the manual what they recommend yet).
While you're doing your forks spend an extra $100 to $160 and upgrade your springs. Manufacturers know most people won't notice suspension weaknesses until after the purchase and they have to keep costs down. They all put in cheaper springs to cut cost AND for the average rider weight.. Whatever that is... Maybe 160#? Springs meant for your riding style and weight make a huge difference. So change oil every two years or if high miles then yearly! At around 25,000 you should pull the forks apart and check/replace bushings too. I order all parts in advance and replace if at all close to needing it. As long as I have it apart it's not a big deal and why go in later to do it?
Something that wasn't mentioned and should be... please use a torque wrench when putting things back together. We are talking about your front wheel and fork assembly. Not good if you lose parts while going down the road. Cheap click types from Harbor Freight are good enough. I use a torque wrench on all bolts on the motorcycle. Yes, they all have torque specs (that's why I have 1/2", 3/8",1/4" drive torque wrenches). If you don't have a Yamaha shop manual where all torque specs are listed let me know. I can take a picture of the page or make a list of torque specs for the job, but just get the manual. You can download one for $25"
I once was working on a bike and I couldn't break loose the fork caps with a 2.5' breaker bar (1/2" drive) and my 6'3" body and I was flexing the handle bars as I was using them for leverage. I finally got out my large impact and that got it loose... and the triple clamp bolts were way over torqued too!
Forks are really not hard and the front wheel IS the hardest part. You can buy some tools to make it easier... such as a spring compressor, a tool to pump the damper and something to set the air gap. Not expensive and if you have none of it then go to TraxxionDynamics.com they have a complete kit for inverted forks for ~$69. Since you are saving over $200 doing it yourself... just get the kit! They also have very good springs with a lifetime warranty.

Guy

Sent from my SM-N960U using Tapatalk
 
Last edited:

audiowize

Active Member
Joined
Sep 29, 2022
Messages
230
Location
Seattle
I just went through the Racetech calculator for respringing my S-10, and they recommend a 0.03gk/mm lighter spring. I don't think I'd ever notice that.

The rear is a whole different story though, it seems way off.
 

TenereGUY

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Joined
Jan 19, 2023
Messages
1,011
Location
Illinois
I just went through the Racetech calculator for respringing my S-10, and they recommend a 0.03gk/mm lighter spring. I don't think I'd ever notice that.

The rear is a whole different story though, it seems way off.
I haven't gotten around to looking at the rear shock yet. Is it adjustable for rebound damping or just preload? Does it have a remote reservoir? TraxxionDynamics.com has some beautiful adjustable shocks for this Tenere. I have been looking. I think I should refill the bank a bit and just ride this bike for a season!

Sent from my SM-N960U using Tapatalk
 

audiowize

Active Member
Joined
Sep 29, 2022
Messages
230
Location
Seattle
With some mini spring compressors, you can compress the spring on the rear shock and slip the retainers off, then install a different spring. I have yet to own a bike where an aftermarket rear shock wasn't a drastic improvement.
 

Highwayman

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Jun 25, 2019
Messages
413
Location
Southern California
I don't see any chance of a shop just replacing oil.... I know I wouldn't touch those at that mileage without putting new seals and bushings in.

If you're doing it, do it.... Order the seals and leave them alone till you can go through em completely. If you're paying someone to do this you're throwing money away for labor and draining only IMHO. Its hardly anything additional at that point to put new seals and bushings in. Fluids, seals and bushings. At that mileage you have a pretty strong case to initiate Murphys Law by changing fluids only.
 

RCinNC

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Joined
Aug 30, 2014
Messages
2,939
Location
North Carolina
For what it's worth as a single data point, I preemptively replaced my fork seals, bushings, etc at 67,000 miles. It really wasn't necessary; nothing had been leaking, and the bushings still looked good. If I hadn't already bought the new parts, I would have been fine just buttoning everything up with the old parts in place. My riding is a pretty good mix of pavement, dirt, and gravel.

I do replace the fork oil every two years. Maybe that contributes to the longevity of the bushings, since any particulate matter in the fork oil gets removed regularly during the oil changes.

I suspect that the fork oil darkens, at least partially, because of heat. I have no idea what the temperature is inside a fork, but oil being constantly compressed and forced through tiny passages has got to generate some heat.

Here's my McGuyver fork spring compressor, made from a cheapie Harbor Freight bar clamp, a trigger clamp, and some aluminum bar stock...


 
Last edited:

TenereGUY

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Jan 19, 2023
Messages
1,011
Location
Illinois
For what it's worth as a single data point, I preemptively replaced my fork seals, bushings, etc at 67,000 miles. It really wasn't necessary; nothing had been leaking, and the bushings still looked good. If I hadn't already bought the new parts, I would have been fine just buttoning everything up with the old parts in place. My riding is a pretty good mix of pavement, dirt, and gravel.

I do replace the fork oil every two years. Maybe that contributes to the longevity of the bushings, since any particulate matter in the fork oil gets removed regularly during the oil changes.

I suspect that the fork oil darkens, at least partially, because of heat. I have no idea what the temperature is inside a fork, but oil being constantly compressed and forced through tiny passages has got to generate some heat.

Here's my McGuyver fork spring compressor, made from a cheapie Harbor Freight bar clamp, a trigger clamp, and some aluminum bar stock...


You have GOT to be an engineer! I love it.

Sent from my SM-N960U using Tapatalk
 

TenereGUY

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Joined
Jan 19, 2023
Messages
1,011
Location
Illinois
With some mini spring compressors, you can compress the spring on the rear shock and slip the retainers off, then install a different spring. I have yet to own a bike where an aftermarket rear shock wasn't a drastic improvement.
Next year a double adjustable penske

Sent from my SM-N960U using Tapatalk
 

Bombadier36

Member
Joined
Aug 8, 2019
Messages
81
Location
Florida Panhandle
Good, you'll be amazed at how stinky and muddy looking that oil will be and how much better the front end will be.
As stated in this thread... many people don't ever change their fork oil out and they should. Also said... how come it looks like that in a sealed system?
If you put a GoPro on your bike so it looks at the forks while running down the road you'll be amazed at the amount of times that forks actually cycle up and down even on what you think is a fairly smooth road. The forks are taking mechanical/kinetic energy and changing it into heat energy. So your fork oil heats up and then when the bike sits it cools down. Fork Seals are not perfect and a small amount of moisture does penetrate and that mixes in with the oil too. A lot of the blackness in the oil is the Teflon coating on the fork bushings wearing off the bushings through friction. It's designed to do that as the Teflon is the sacrificial coating. You want that to wear instead of the forks aluminum tube. If you keep riding and don't service your forks the Teflon wear is accelerated and then the inside of the fork tube starts to wear and that causes problems. Your fork tube wears as it is softer than the steel bushing. I know Honda says to change the bushings if 3/4 of the Teflon is gone. (My 1st Yamaha and I haven't read in the manual what they recommend yet).
While you're doing your forks spend an extra $100 to $160 and upgrade your springs. Manufacturers know most people won't notice suspension weaknesses until after the purchase and they have to keep costs down. They all put in cheaper springs to cut cost AND for the average rider weight.. Whatever that is... Maybe 160#? Springs meant for your riding style and weight make a huge difference. So change oil every two years or if high miles then yearly! At around 25,000 you should pull the forks apart and check/replace bushings too. I order all parts in advance and replace if at all close to needing it. As long as I have it apart it's not a big deal and why go in later to do it?
Something that wasn't mentioned and should be... please use a torque wrench when putting things back together. We are talking about your front wheel and fork assembly. Not good if you lose parts while going down the road. Cheap click types from Harbor Freight are good enough. I use a torque wrench on all bolts on the motorcycle. Yes, they all have torque specs (that's why I have 1/2", 3/8",1/4" drive torque wrenches). If you don't have a Yamaha shop manual where all torque specs are listed let me know. I can take a picture of the page or make a list of torque specs for the job, but just get the manual. You can download one for $25"
I once was working on a bike and I couldn't break loose the fork caps with a 2.5' breaker bar (1/2" drive) and my 6'3" body and I was flexing the handle bars as I was using them for leverage. I finally got out my large impact and that got it loose... and the triple clamp bolts were way over torqued too!
Forks are really not hard and the front wheel IS the hardest part. You can buy some tools to make it easier... such as a spring compressor, a tool to pump the damper and something to set the air gap. Not expensive and if you have none of it then go to TraxxionDynamics.com they have a complete kit for inverted forks for ~$69. Since you are saving over $200 doing it yourself... just get the kit! They also have very good springs with a lifetime warranty.

Guy

Sent from my SM-N960U using Tapatalk
Finished the fork maintenance along with some other stuff (throttle cable and coolant change). Amazed how different the bike feels! The front end feels more responsive and smooth. Thank you for all of the information. I’m didn’t grow up with or have a ton of experience mechanically. The information was helpful. Any of the mistakes or broken things were my own doing :)
 

TenereGUY

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Joined
Jan 19, 2023
Messages
1,011
Location
Illinois
Finished the fork maintenance along with some other stuff (throttle cable and coolant change). Amazed how different the bike feels! The front end feels more responsive and smooth. Thank you for all of the information. I’m didn’t grow up with or have a ton of experience mechanically. The information was helpful. Any of the mistakes or broken things were my own doing :)
We all gotta start somewhere and forums like this are here to help us along the path of learning! Did you upgrade your fork springs over just do oil? Did you get the kit to do the forks?
 

Bombadier36

Member
Joined
Aug 8, 2019
Messages
81
Location
Florida Panhandle
We all gotta start somewhere and forums like this are here to help us along the path of learning! Did you upgrade your fork springs over just do oil? Did you get the kit to do the forks?
No spring upgrade and no oil weight changes either. Changed all the seals, etc. while it was apart. Oil was dirtier than I expected. My wrench slipped when tightening the fork cap. Next time I’ll have to replace it. Learned a lot along the way though so that was really valuable.
 

TenereGUY

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Joined
Jan 19, 2023
Messages
1,011
Location
Illinois
No spring upgrade and no oil weight changes either. Changed all the seals, etc. while it was apart. Oil was dirtier than I expected. My wrench slipped when tightening the fork cap. Next time I’ll have to replace it. Learned a lot along the way though so that was really valuable.
I specifically used my 6 sided impact socket to ensure no slippage. Used it with a torque wrench, not an impact! Many times there is a used tool resale shop and you can go find bins of individual sized sockets. That way you don't have to buy a
 

7KALITT4KRAZY7

New Member
Joined
Feb 8, 2023
Messages
20
Location
Dothan, AL.
New Super Ten rider, and not a very patient mechanic. Just bought my 2014 non-es and after riding 600 miles. I’ve noticed the front forks take a pretty good nose dive when I I really get on the brakes. I’ve referenced google university and adjusted accordingly. But still seems soft, mushy and weak. Im in the books for a complete fluid change in July and wondering if I should add a front fork renewal. Thanks for sharing any wisdom and advise.
 

jrusell

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Joined
Aug 23, 2017
Messages
460
Location
Dartmouth, Nova Scotia, Canada
New Super Ten rider, and not a very patient mechanic. Just bought my 2014 non-es and after riding 600 miles. I’ve noticed the front forks take a pretty good nose dive when I I really get on the brakes. I’ve referenced google university and adjusted accordingly. But still seems soft, mushy and weak. Im in the books for a complete fluid change in July and wondering if I should add a front fork renewal. Thanks for sharing any wisdom and advise.
New fork oil will help, but the S10 comes stock with soft progressive springs that contribute to the dive you are experiencing.
A good set of straight rate springs will greatly help with your issue. Stoltec Moto or Sonic springs sells a replacement set of straight rate springs for $120/pair and are worth every penny.

A short term fix is to dial in some more preload on the fork caps. This will pick up the front of the bike slightly and help reduce the diving you are experiencing.
 

7KALITT4KRAZY7

New Member
Joined
Feb 8, 2023
Messages
20
Location
Dothan, AL.
New fork oil will help, but the S10 comes stock with soft progressive springs that contribute to the dive you are experiencing.
A good set of straight rate springs will greatly help with your issue. Stoltec Moto or Sonic springs sells a replacement set of straight rate springs for $120/pair and are worth every penny.

A short term fix is to dial in some more preload on the fork caps. This will pick up the front of the bike slightly and help reduce the diving you are experiencing.
Thanks Jrusell. I’ll definitely purchase the Stoltec Moto or Sonic springs. What a relief that this is normal and not some catastrophic issue.
 
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