Are cartridge emulators worth while?

MisterBigWheel

Member

Oct 7, 2010

35

1

• Nov 30, 2010

• #1

I know this is a question from rather far in left field.

But. I have Yamaha Tri-Z (yes, the three-wheeler) forks mounted to a motorcycle. (no, I'm not married to my cousin)

Race Tech makes cartridge fork emulators that would fit in these 39mm conventional forks.

My question is this: Considering that these forks are terrible by modern standards, would it make a dramatic improvement to the forks performance to install the emulators?

Regards,

Mr. BigWheel

 

whenfoxforks-ruled

Old MX Racer

~SPONSOR~

Oct 19, 2006

8,129

2

Merrillville,Indiana

• Dec 1, 2010

• #2

Personally untested. I have heard nothing bad. Not a BIG fan of race tech, but they seem to be the only ones picking the pockets of older bike owners? There are valving components that go inside, and there are outside bladder type add ons, thats the one I have. The inside parts SHOULD be WAY better. Hey, that 3 wheeler is dangerous. Vintage Bob

 

MisterBigWheel

Member

Oct 7, 2010

35

1

• Dec 3, 2010

• Thread starter
• #3

Bob,

At least 3 wheelers don't fall over when you stop them. But the forks are mounted on a bike and not a trike anyway.

I have Moose Racing handlebars that have the bladder and a restricting valve and a bleeder. I was just wondering if there was any point to trying to go further with these old forks.

Regards,

Mr. BigWheel

 

whenfoxforks-ruled

Old MX Racer

~SPONSOR~

Oct 19, 2006

8,129

2

Merrillville,Indiana

• Dec 3, 2010

• #4

Fox used to make different dampening rods and air cap kits. I have seen some of these still for sale, reasonable on fleabay. The bladder tanks I have, no pressure on the fork side, and up to 100 psi or so on the other side. It has a schrader valve on each side.

 

D

dirt bike dave

Sponsoring Member

May 3, 2000

5,348

3

• Dec 3, 2010

• #5

I've used the emulators on an '90 KDX and my buddy had his on an '89. On the KDX, the emualtors made a HUGE improvement.

FWIW, the stock forks on the KDX had way too much high speed compression damping and way too soft a spring. So when you hit a sharp root or rock, you got a huge jolt, but the suspension sucked on big hits and whoops due to the soft springs. Combined with stiffer springs, the emulators fixed all the problems. Not modern fork good, but way way better than stock.

 

MisterBigWheel

Member

Oct 7, 2010

35

1

• Dec 5, 2010

• Thread starter
• #6

Thanks for the responses guys. I'll start looking into these things because my forks could use some help. I have some Progressive springs that I hope will be the correct rate and will be installed with some new seals and heavier weight oil. The KDX has about the same level of technology, so that's a great reference point.

The reservoir handlebars have a bleeder valve in them to relieve pressure like I have in my KTM300xc forks. Is it a bad idea to run 0 pressure in these old school forks?

Regards,

Mr. BigWheel

 

whenfoxforks-ruled

Old MX Racer

~SPONSOR~

Oct 19, 2006

8,129

2

Merrillville,Indiana

• Dec 5, 2010

• #7

It is a REALLY BAD idea to run any pressure in them old school forks/ any fork. Run zero pressure, and when you relieve the pressure, make sure the wheel is off the ground. What ever spring you need in the rear, goes into the front. Matching the valving to the style and spring would always be nice!

 

P

pesky nz

Member

Sep 13, 2010

296

0

• Dec 5, 2010

• #8

I also have an old tri-zed and the forks on it have the axle trailing behind the fork legs and a lot of off-set on the triple clamps to achieve correct rake and trail so if you have the same forks as my trike you may have some geometry issues. Emulators are definitely a major improvement. As you are in a mix and match situation it may be difficult to get your emulators right without some experimentation ( tuning)

 

D

dirt bike dave

Sponsoring Member

May 3, 2000

5,348

3

• Dec 5, 2010

• #9

OP - The emulator's compression damping can be adjusted, but you have to pull the fork springs out to get to them.

Don't forget about oil level and oil weight when tuning. Oil level makes a big difference in bottoming resistance and stiffness as the forks get close to bottoming out (higher oil = harder to bottom). Oil weight mainly impacts rebound damping. Heavier oil = slower rebound.

Spring pre-load can also be a useful adjustment. I had a slow steering KDX 250 and handling was improved by running no spring pre-load on the forks.

 

MisterBigWheel

Member

Oct 7, 2010

35

1

• Dec 6, 2010

• Thread starter
• #10

Pesky,

You are absolutely correct about the geometry. The original forks were semi-leading axle forks with no underhang and the Tri-z forks have a ton of underhang, trailing axles and a pronounced rake. The '86 Tri-Z triple clamps have even more rake designed into them.

The bike is used almost exclusively in the snow, though, and the increased stability is appreciated. The trails are generally not very technical and it helps when the bike has to plow through a thousand ruts left by the snowmachines out on the rivers..

Regards,

Mr. BigWheel