race tech gold valve issue

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g2501

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Joined
Dec 25, 2017
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Location
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hi everybdy,
after searching for something about 1 year for a cheap upside-down front fork conversion finally I convinced myself that an original fork good restoration / upgrade was the best way to go.
In order to chieve a good result I changed almost everything except the main tube and the stachions.
I purchased:
racetech 0.95 kg/mm springs
racetech gold valve
SKF rubber seals
all-balls bronze seals and clips kit
Liquy-Moly fully sinthetic 10W fork oil

As recommendend I've made the new 4 holes and enlarged the original rebound hole on the dampers at 8mm. I've mirror finish the tubes before re-installation and deeply clean all the parts.

Everything was pretty easy to re-build , and I've follow carefully the recommendations for the gold valves springs color and preload , for oil level and for new spacer lenght, but here comes the trouble...

My brand new restored fork is stuck.... no damping at all.

Tried to remove the gold valve emulators and suddenly the fork starts working correctly ( it flows down with the weight of the bike) ...but this time too much.
Unfortunately since I've enlarged the original rebound holes ( ...and made the additional holes) I cannot return to my original configuration , so I was forced to try all the gold valves springs and pre-load settings.

even pushing the fork tube before the reinstallation gives me no feedback at all.
My mechanich is pretty sure that this issue is related to the gold valve emulators, but so far I've never heard or read any issue about them.

Since the gold valves are pretty simple I also tried to dismount them and clean them, but as you can easily imagine there was no changes at all regarding the behaviour of the forks.

Right now I have the silver ( lighter ) springs with 7 turns preload , swapped back to the original steel spring spacers ( shorter than the suggested racetech spacer ) and still my bike is very rigid in the front.
Every small bump or hole is a pain for my wrists , and I'm starting to worry about the triple tree bearings ( chenged some months ago)

did someone of you had a similar issue? what can I try?
 
Hi MaxMidnight, no I've only followed the suggested spacer lenght to leave 25mm of pre-load.
with this setup the front fork was completely stuck.

I had to change gold valve spring and lower the fork preload to 20mm using the original yamaha spring spacer instead of the racetech PVC.
with this configuration I can see some small changes in the fork when I remove the security stands under the bike and let it touch the ground.

With gold valve yellow spings + 2 turns preload + 4 holes plates and the suggested lenght for the springs spacer the front fork doesn't move even with my weight on it ( 187lb more or less )
 
You did not mention how much (or how high of an oil level when measuring from the top of the fork with the caps off, and no springs in the forks) oil in the forks. If you have the forks over-filled with oil, then you'll be causing a hydraulic lock and they will not compress as expected. Oil level/amount is crucial for proper damping and compressing of the forks.

Vinnie
 
Hi Vinnie, i don't remember the exact oil level, but for what I can remember I had the racetech instructions that came with the code in the box.
I used the code on the racetech website to access the form , filled up all data with my weight , spring rate, ecc,ecc and with my mechanic I leveled the oil exactly as stated.
Aniway this is a test that I haven't done yet, and is a good advice, thanks.
Tomorrow morning I will go to the garage and made some new test trying to remove an equal amount of oil on bothforks.
Will start removing 1cc of oil and then close to see if there are some differences.
do you have any suggestions about this test? is ok 1cc of oil less or do you think that I should remove more oil?
 
Before removing the oil, I would open the forks (with no weight on them of course), and remove the springs. Then use a rod or some other mechanism that you can put down into the fork and see what measurement you get from just where the rod touches the level of the oil to the top of the fork. The measurement should be somewhere around 123mm (for your '96 Vmax with 41mm forks) from the oil level in the fork to the top of the fork tube without the cap on.
Again, remove the spring from the fork, and the forks should be fully compressed when measuring this way.
Vinnie
 
Before removing the oil, I would open the forks (with no weight on them of course), and remove the springs. Then use a rod or some other mechanism that you can put down into the fork and see what measurement you get from just where the rod touches the level of the oil to the top of the fork. The measurement should be somewhere around 123mm (for your '96 Vmax with 41mm forks) from the oil level in the fork to the top of the fork tube without the cap on.
Again, remove the spring from the fork, and the forks should be fully compressed when measuring this way.
Vinnie

I believe you have a fundamental error there, the '85-'92 were 40 mm and '93-'07 were 43 mm downtubes.
 
Note that you set the oil level with the springs out AND the forks bottomed out.
I use a syringe with an appropriate length of tube attached to remove oil to the correct level.
Early forks should be 140mm below the top of the fork tube and 160mm on the later.
Don't be tempted to just 'remove a bit of oil', do it correctly so you know the correct ammount is in there.

Also note that Racetech recommend a different weight for the ealy and later forks.

Once you have got that correct set the static sag; the suggested tube length is only a starting point.
Setting the static sag makes a huge difference to the feel of the forks and if you ignore this step you will have done only half the job.

Once you have the basics correct only then should you try and fine tune the system.
IMO what comes out of the box will be good enough for the majority of riders.
 
Hello everybody , first of all thank you for all the suggestions, they will come very useful from now on .
Long story short ; mistery solved!!!
Today after I remove the gold valves from the fork tubes I noticed something that I believed to be useless but it was the main cause of this issue. I forgot to mount the clip on the race tech valves.
Believe me or not , but even if I can’t understand why , after I installed the clip and reassemble the fork everything went good.
Now I have a fully functional suspension on my bike.
Now I will try to use the correct length spring spacer (the longer pvc spacers sent me with the new race tech springs) and check the static sag as suggested, but knowing that the gold valves are working correctly it will be more easy.
 

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g2501 it seems like you've got this sorted. I've been lurking and watching this thread with some vested interest. Thanks to all that contributed to this post. Lot's of good info there. I installed race tech gold valves and progressive springs in my 98 many years ago but was never completely happy with the result. I was riding 2 up a lot at the time and think I might have set the emulator valves too stiff. I mostly ride solo these days and get some knocking that sounds like the forks are rebounding too much. I envision that the valves must be riding on top of or not deep enough in the fork oil to properly address rebound. I believe I also went with a heavier fork oil when I did them, which may be a further contributing factor. I don't recall what the weight was but think the Bell Ray bottle is still on a shelf somewhere in the garage! Seems like the knocking has gotten worse over time but it might just be my mind playing tricks on me. And the roads around here seem to get worse each year, especially the back roads that I prefer to cruise on! At one point I thought my head bearings were going but recently checked them out and they seem smooth and no play or unwanted movement in the goose neck. I remember most everything from this string on the steps, including using a big syringe with a tube with a mark on it to set the right fluid level. One thing I don't remember is those clips! I also don't remember them coming with different color springs. I'm going to tear my forks down this winter and go through them. I still have the original instructions somewhere but I'll definitely bookmarking this string to come back to and reference during the process. I'm hoping that I'll just need to back off the setting on the emulators and make sure I just the right weight fork oil. Hopefully nothing's damaged in there from the over rebounding knocking. It's getting cold here in Atlantic Canada but I'm hoping to get a couple of more short rides in before the roads crews start salting and sanding the roads! I'll tackle it in a few weeks. If anyone has any info or advice on the over rebounding that I'm getting, I'd love to hear from you.
 
Before tearing things apart (unless you are bored), and now I'll do my cracked record impression, check the Static Sag!

After I fitted springs and emulators into mine, going over sudden bumps in the road was painful due to the shock that came up through the bars...set the sag and the problem was gone.

Having had that experience is why I am an evangelist for setting the SS.
 
well , da_yammie , at elast I'm happy that this issue has become a good information poit for who had an issue with the gold valve emulators.
To be honest it was my fault but being Italian it's sometimes not an easy task to fully understand the instructions. Plus , keep in mind that I live in a small country where motorcycle guys almost never heard of "gold valve" ( to be honest they never heard of a "v-max" too... but that's another story )
MaxMidnight, for sure I will follow your suggestions , just will take my time to do things well and not like in a hurry like this time.
It tooks me 4 months to collect all parts at a bargain price and as soon as I had everything in my hand I was looking forward to have everything in place... and had my wife angry like a mad cat due to all spare parts all over the apartment.
All in all I feel that keeping the original 43mm fork was the best choice, for less than half the price I have now a good and almost brand new fork, perfect for the old gen1 v-max, so it depends only on me to achieve a perfect result.
Just one last thing, I found the racetech data sheett stating the correct static sag.
I will write down hoping this will help other maxxers. just keep in mind that I replaced the original springs with the racetech springs 0.95Kg/mm, I weight 85kg and I choose the Touring : intermediate /B class and standard stiffness
Fork Oil : OSFO 20
Oil level : 140mm
Spring rate : 0.92Kg/mm
Fork spring preload : 25mm
Front sag : 35mm
Compression adjuster : n/a
Rebound adjuster : n/a
 
Suggest you read the instructions again, Racetech give a value of between 15 & 30 mm...I would aim for somewhere between 25 mm (firmer ride) and 30 mm (softer ride).

Use large washers to go on top of the preload spacer if you want to reduce the sag.
 
Before tearing things apart (unless you are bored), and now I'll do my cracked record impression, check the Static Sag!

After I fitted springs and emulators into mine, going over sudden bumps in the road was painful due to the shock that came up through the bars...set the sag and the problem was gone.

Having had that experience is why I am an evangelist for setting the SS.

Thanks for the advice. I'll check the SS before I rip anything apart.
 
I'm sure everyone's aware of this but just in case:

Years ago, on GP race bikes, we used a very thin tie-wrap (zip tie) on the fork leg to accurately measure both sag and deflection / travel. A tight, oil-soaked, piece of string can do the same job, as long as it's tight on the fork stanchion.
 
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