Revalve, broken peening. Game over?

[kjetil4455]

Hi guys

So I went ahead and bought the stoltech revalve package and linear spring install. It didn't come with instructions, but I went ahead and got this done at the local yamaha shop.
We disassembled the inner chambers and loosened the nuts. As the nuts came off, a part of the peening broke. But we changed the valves and screwed the nut back on with red locktite. Seemingly, enough thread was still available and we didn't think much of it.

First ride seemed very smooth. Until I jumped the bike off a small obstacle... I heard an immediate clunk as I left the ground (ie. as the fork extended fully), I could also feel it in the handlebars. Later I popped a small wheelie and could once again feel the obvious clunk. See video: https://drive.google.com/file/d/1spm2QuZGocYZqirrly86hsufx5KFxAUn/view?usp=sharing

I started googling and realized that some other people have had similar symptoms from the nuts unscrewing themselves from the stems and exploding all ove the inner chambers. Reading this made me really worried. I just think it's strange how it would unscrew itself, if so is the case, so quickly, after like 30 minutes of riding.

How screwed am I? It will cost me more than a grand to buy new piston kits and new stoltech valve kits.

 

[blitz11]

You can buy the compression valve holders from Traxxion Dynamics and other vendors (lanier suspension has them for some KYB shocks), or maybe even technical touch.

You could also have a competent machine shop make a replacement piece out of 6061-T6 AL.

"Unpeening" is a delicate job requiring both patience and skill.

I'd pull the fork apart and check the status. Pull the compression valve holder, check its status, and find some new ones if necessary.

 

[~TABASCO~]

Ive performed this several times... If you take it back part, please post a few photos so people can see the exact status of the situation ! Sometimes the problem or solution is found in the very small 'details'......

 

[kjetil4455]

Thanks guys. I just cannot fathom that it would tear apart within 30-60 minutes of gentle riding; we used red locktite and it seemed to brace the threads just fine when torqueing it. As far as I could see, there was sufficient amount of remaining thread for it to bite on to.

But, again what else could it be...

 

[~TABASCO~]

Thanks guys. I just cannot fathom that it would tear apart within 30-60 minutes of gentle riding; we used red locktite and it seemed to brace the threads just fine when torqueing it. As far as I could see, there was sufficient amount of remaining thread for it to bite on to.

But, again what else could it be...

"It sounds" like it did not back out but something broke.... Should be evident when you take it apart.... Its all speculation until its taken apart, cleaned and evaluated...

By your video, personally I would suggest NOT riding until it's looked at...

 

[kjetil4455]

"It sounds" like it did not back out but something broke.... Should be evident when you take it apart.... Its all speculation until its taken apart, cleaned and evaluated...

By your video, personally I would suggest NOT riding until it's looked at...

Agreed, will open it tomorrow. God damnit.

 

[~TABASCO~]

Reading and watching your video again. It might be the bottom out spring that broke or somehow is damaged... That 'clicking' sound is the bottom out spring. Ive changed my bottom out springs to much stiffer springs in the past. I had to equal the stiff main spring set up I use.

By the look of your video, and you pushing on the front end.... It "looks" very soft for off-road use.... What spring value have you installed ? What weight oil, and height of oil? Also, if you're using an aftermarket spring, what lengths was the spring preload spacer cut? This spacer length is critical for the overall stroke and spring performance.... If you did not do the work, these questions are really important....

After market straight wound springs are shorter than stock, if the cut spacer is to short, and the front tire comes off the ground, Im thinking the load could be taken off the rebound into "free wheel" and smash the bottom out springs and other components in that area...... (Im just thinking out loud)

 

[kjetil4455]

Reading and watching your video again. It might be the bottom out spring that broke or somehow is damaged... That 'clicking' sound is the bottom out spring. Ive changed my bottom out springs to much stiffer springs in the past. I had to equal the stiff main spring set up I use)

By the look of your video, and you pushing on the front end.... It "looks" very soft for off-road use.... What spring value have you installed ? What weight oil, and height of oil? Also, if you're using an aftermarket spring, what lengths was the spring preload spacer cut? This spacer length is critical for the overall stroke and spring performance.... If you did not do the work, these questions are really important....

After market straight wound springs are shorter than stock, if the cut spacer is to short, and the front tire comes off the ground, Im thinking the load could be taken off the rebound into "free wheel" and smash the bottom out springs and other components in that area...... (Im just thinking out loud)

I agree but Nick at Stoltech insisted that an 85Nm spring woud be good for my weight (220lb) and that I could simply increase oil height if I was struggling with bottoming out. I told him after installation that I was barely reaching spec sag even at max preload, but he insisted that his experience was 85Nm for my weight even for hard offroading. I bought the spring and the valve package.

The oil weight is 16 CTs, which is the same as Yamaha 01. This is what he recommended for the valve package he sold me. It came with the kit.
The oil level should be 150mm, but seeing as we dried the entire fork out and we don't have a cartridge compressor, we just put 485mL in there.

The main clunking happens at extension. I don't really hear anything when I go into compression. I can jump the bike up and down and, nothing. But once it goes into full extension it clacks as it begins to compress. There must be something that's loose as it reaches full extension

 

[kjetil4455]

Could it be that the yamaha tech, as we rushed a little at the end, got the sequence wrong with regards to the piston bearing, spacer, washer etc?

 

[~TABASCO~]

I agree but Nick at Stoltech insisted that an 85Nm spring woud be good for my weight (220lb) and that I could simply increase oil height if I was struggling with bottoming out. I told him after installation that I was barely reaching spec sag even at max preload, but he insisted that his experience was 85Nm for my weight even for hard offroading. I bought the spring and the valve package.

Do you know if that spring is a .85 / .90 / .95 / 1.0 / Etc ? I cant convert this second...

 

[~TABASCO~]

I agree but Nick at Stoltech insisted that an 85Nm spring woud be good for my weight (220lb) and that I could simply increase oil height if I was struggling with bottoming out. I told him after installation that I was barely reaching spec sag even at max preload, but he insisted that his experience was 85Nm for my weight even for hard offroading. I bought the spring and the valve package.

The oil weight is 16 CTs, which is the same as Yamaha 01. This is what he recommended for the valve package he sold me. It came with the kit.
The oil level should be 150mm, but seeing as we dried the entire fork out and we don't have a cartridge compressor, we just put 485mL in there.

The main clunking happens at extension. I don't really hear anything when I go into compression. I can jump the bike up and down and, nothing. But once it goes into full extension it clacks as it begins to compress. There must be something that's loose as it reaches full extension

I would start at the bottom out spring.... "my mind tells me"......... from you describe -

 

[kjetil4455]

I would start at the bottom out spring.... "my mind tells me"......... from you describe -

It's not bottoming out. It happens on extension.

 

[kjetil4455]

Do you know if that spring is a .85 / .90 / .95 / 1.0 / Etc ? I cant convert this second...

sorry, yes, it's 0.85 kg/mm

 

[~TABASCO~]

Could it be that the yamaha tech, as we rushed a little at the end, got the sequence wrong with regards to the piston bearing, spacer, washer etc?

ANYTHING is possible...... All speculation at this point -


I dont know the spring rate currently in the OD of the coil.... I would not agree with the weight of the oil.... I dont agree with just add more oil for the compression with your weight.......

When (a mechanic) cleans and pull the whole fork apart and washes and dries everything... (this is excellent)... when you add oil back it can be very difficult to 100% get all the air out of the cartridge (both) and to check and re check / re check / re check, the oil height......... Im very particular and have found this to fluctuate as air works its way out of the 'system'...... some folks pour in the 'amount' and button it all up and send someone down the road...... (Im NOT suggesting anyone has done this) I have found this "prescribed amount" of oil always to end up being WRONG.....
It takes time to get that air out and to make sure it's out.... Most shops do not spend that extra time. **IF** air is left in the cartridge it could be bad because there would be no resistance being pushed though the valve stack and would slam the bottom out springs....

(once again, just thinking out loud...... ALL speculation at this point )

 

[~TABASCO~]

It's not bottoming out. It happens on extension.

Correct...... It will bottom out in full extension... You have little springs inside the fork to dampen the full extension.. they are about 3-4" (101.6 mm) in length..... They are in the cartridge on both sides...

 

[~TABASCO~]

sorry, yes, it's 0.85 kg/mm

IMOP...... WAY too small (soft) for off road and your weight....... NO DOUBT ! IMOP, you should be at a 1.0 or larger with thicker weight oil, Etc, Etc, Etc.. Also, the length of the spacer you can add a few mm to for some tuning.....

Side note, If you want decent off road with having a pretty compliant 'road' ride, I would suggest a minimum of .95 spring...

.85 and stock (01) oil weight is just new "stock" stuff...... that's stock factory soft stuff...............

 

[kjetil4455]

IMOP...... WAY too small for off road and your weight....... NO DOUBT ! IMOP, you should be at a 1.0 or larger with thicker weight oil, Etc, Etc, Etc.. Also, the length of the spacer you can add a few mm to for some tuning.....

Side note, If you want decent off road with having a pretty compliant 'road' ride, I would suggest a minimum of .95 spring...

.85 and stock (01) oil weight is just new "stock" stuff...... that's stock factory soft stuff...............

I also thought it sounded weird, but I explained in detail what I wanted and, seeing as this guy has great reviews all over this forum, I decided to trust him. Regardless, my main concern right now is wheether or not my fork is fucked. I could always change to another spring.

 

[kjetil4455]

Correct...... It will bottom out in full extension... You have little springs inside the fork to dampen the full extension.. they are about 3-4" (101.6 mm) in length..... They are in the cartridge on both sides...

Interesting. Is this spring inside of the cartridge, then? I didn't see it in the main chamber like I did on my bike that has a dampener rod.

 

[~TABASCO~]

Interesting. Is this spring inside of the cartridge, then? I didn't see it in the main chamber like I did on my bike that has a dampener rod.

I believe I still have my first set... I can show you a photo.....

 

[~TABASCO~]

Very fast GOOGLE explanation.... I miss spoke... Not a bottom out spring..... Its a Top out Spring.... Sorry.....

I think when this is taken apart it will be evident...... If not, start looking at the 'top out spring' area.....