Front Fork Cartridge Emulator - RD500 ForkPiston Diameter ?

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rd84
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Front Fork Cartridge Emulator - RD500 ForkPiston Diameter ?

#1 Post by rd84 » Mon Aug 21, 2017 6:01 am

Hi,

I'm thinking about getting some cartridge emulators for the forks - can anyone tell me the outside diameter of the standard fork piston please.

Thanks

Regards
Paul

smokamoto
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Re: Front Fork Cartridge Emulator - RD500 ForkPiston Diamete

#2 Post by smokamoto » Mon Aug 21, 2017 1:30 pm

Hello Paul,

I don't know what the piston measures at however I bought the cartridge emulators from Race Tech, part number FEGV S3501, $170.00 US list price. Have yet to install them in my RZ but have put them in my '01 FZ-1, '06 Ninja 500, and '92 FJ-1200.
Are you concerned about fitment problems?

rd84
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Re: Front Fork Cartridge Emulator - RD500 ForkPiston Diamete

#3 Post by rd84 » Mon Aug 21, 2017 2:43 pm

smokamoto wrote:Hello Paul,

I don't know what the piston measures at however I bought the cartridge emulators from Race Tech, part number FEGV S3501, $170.00 US list price. Have yet to install them in my RZ but have put them in my '01 FZ-1, '06 Ninja 500, and '92 FJ-1200.
Are you concerned about fitment problems?
The supplier in the U.K. asked me for the dimensions so he can choose the correct unit which I think is by YSS

Thanks

Cheers
Paul

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1601pete
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Re: Front Fork Cartridge Emulator - RD500 ForkPiston Diamete

#4 Post by 1601pete » Mon Aug 21, 2017 4:23 pm

Paul

What do they do?

Thanks

rd84
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Re: Front Fork Cartridge Emulator - RD500 ForkPiston Diamete

#5 Post by rd84 » Mon Aug 21, 2017 6:12 pm

1601pete wrote:Paul

What do they do?

Thanks
Hi Pete,

Well - allegedly they give far superior damping compared to our old 500's damping - they are supposed to emulate modern cartridge forks - I think the damping can support the forks to some degree so that a softer spring than otherwise can be used.

Cheers
Paul

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1601pete
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Re: Front Fork Cartridge Emulator - RD500 ForkPiston Diamete

#6 Post by 1601pete » Mon Aug 21, 2017 6:26 pm

Ok thanks.

I'd be interested in your progress with this.

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phildu31
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Re: Front Fork Cartridge Emulator - RD500 ForkPiston Diamete

#7 Post by phildu31 » Mon Aug 21, 2017 7:20 pm

1601pete wrote:Paul

What do they do?

Thanks

In RD/RZ forks, damping is controlled by oil viscosity.
And a change in oil viscosity affects simultaneously rebound damping, low-speed compression damping and high-speed compression damping.
Due to fluid mechanics, high speed compression damping is very higher than low speed compression damping, which is the opposite of what should be.
( high speed compression comes from irregularities of the road )

With cartridge emulator, oil viscosity only affects rebound damping which should only be adjusted accordingly to the stiffness of the springs.
And compression damping is controlled by the cartridge which permits high speed compression damping lower than low speed compression damping.
Unfortunately, low speed compression and high speed compression damping can't be adjusted separately with these cartridges.

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1601pete
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Re: Front Fork Cartridge Emulator - RD500 ForkPiston Diamete

#8 Post by 1601pete » Mon Aug 21, 2017 7:32 pm

Paul

I'm assuming you have seen this?

http://racetech.com/ProductSearch/2/Yam ... LC/1984-89" onclick="window.open(this.href);return false;

Started this on FB. They seem popular

https://www.facebook.com/groups/practic ... 008378857/" onclick="window.open(this.href);return false;

rd84
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Re: Front Fork Cartridge Emulator - RD500 ForkPiston Diamete

#9 Post by rd84 » Tue Aug 22, 2017 6:54 am

Hi Pete,

Thanks very much for the above info.

Cheers
Paul

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Re: Front Fork Cartridge Emulator - RD500 ForkPiston Diamete

#10 Post by Ron57 » Sat Aug 26, 2017 6:04 am

Hi came across these aftermarket suspension for the RZ500
http://store.suspensionshop.org/yamaha/ ... -1989.html" onclick="window.open(this.href);return false;
Cheers Ron.

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Re: Front Fork Cartridge Emulator - RD500 ForkPiston Diamete

#11 Post by rd84 » Sat Aug 26, 2017 9:01 am

phildu31 wrote:
1601pete wrote:Paul

What do they do?

Thanks

In RD/RZ forks, damping is controlled by oil viscosity.
And a change in oil viscosity affects simultaneously rebound damping, low-speed compression damping and high-speed compression damping.
Due to fluid mechanics, high speed compression damping is very higher than low speed compression damping, which is the opposite of what should be.
( high speed compression comes from irregularities of the road )

With cartridge emulator, oil viscosity only affects rebound damping which should only be adjusted accordingly to the stiffness of the springs.
And compression damping is controlled by the cartridge which permits high speed compression damping lower than low speed compression damping.
Unfortunately, low speed compression and high speed compression damping can't be adjusted separately with these cartridges.
Hi Phil,

Thanks very much for this detailed explanation - very interesting and informative

Cheers
Paul

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Re: Front Fork Cartridge Emulator - RD500 ForkPiston Diamete

#12 Post by rd84 » Sat Aug 26, 2017 9:06 am

Ron57 wrote:Hi came across these aftermarket suspension for the RZ500
http://store.suspensionshop.org/yamaha/ ... -1989.html" onclick="window.open(this.href);return false;
Cheers Ron.
Thanks for that Ron

Cheers
Paul

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Re: Front Fork Cartridge Emulator - RD500 ForkPiston Diamete

#13 Post by rd84 » Sat Aug 26, 2017 9:26 am

Just for the record by measurement and from the manual..

Springs 28.55mm diameter 498mm long limit 493mm long
Stroke 140mm
K1 0 to 95mm 0.79kg/mm
k2 95 to 115mm 1.04 kg/mm
k3 115 to 140mm 2.45kg/mm

Oil Capacity 300cm3 SAE 5W

Weight of Bike with Full Fuel Tank 205kg

Fork Tubes - measured at the top thread
Outside diameter 37mm
Inside diameter 29.6mm

Damper Rod
28.68mm diameter for 14.9mm at the top
17.48mm diameter for 223.5mm at the bottom
Total length 238.4mm

Hopefully this is enough information to order your front fork upgrades

Cheers
Paul
Last edited by rd84 on Sat Aug 26, 2017 11:18 am, edited 1 time in total.

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phildu31
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Re: Front Fork Cartridge Emulator - RD500 ForkPiston Diamete

#14 Post by phildu31 » Sat Aug 26, 2017 10:53 am

Hi.
Outside diameter of fork tubes is 37 mm.
It is reduced to 36 mm at 60 mm of top on 47X bikes and at 200 mm 1GE bikes.
So different references for inner tubes in parts list.

rd84
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Re: Front Fork Cartridge Emulator - RD500 ForkPiston Diamete

#15 Post by rd84 » Sat Aug 26, 2017 11:21 am

phildu31 wrote:Hi.
Outside diameter of fork tubes is 37 mm.
It is reduced to 36 mm at 60 mm of top on 47X bikes and at 200 mm 1GE bikes.
So different references for inner tubes in parts list.
Thanks Phil - I've edited my post above.

Don't know what happened there ? ?

Cheers
Paul

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