New Zongshen RX3 (ZS250GY-3) Dual Sport

[Huck369]

Originally Posted by SpudRider

My Taobao shipment has cleared customs. Now it is only a short trip by U.S.P.S. Priority Mail to East Idaho.

Looking forward to your review of the LED Headlight

[SpudRider]

Rest assured, gentlemen and ladies, you at China Riders will be the first to hear my review of the upgraded, two LED headlight for the RX3.

[rjmorel]

Originally Posted by SpudRider

As FastDoc might say, the prognosis is optimistic. I am going out in a few minutes to tighten the spring preload another three turns.

Spud, I've been wondering about my suspension and how to make it ride less harsh on the street. I weigh around 180 w riding gear and the pot holes on Walla Walla streets are bad. When I hit them sitting down it really rattles the old back bones. I have less then 100 miles on the RX3 so it's not broke in yet and I thought I'd wait 500-700 miles before doing any adjustments to change things.
On the rear shock is the preload changed by just turning the ring under the spring? Is there any set screw locking said ring? Any special tool used to turn ring?
I don't know squat about adjusting suspension like racers do but I'm assuming I want the least amount of preload so it's not as harsh and squats down more. Then adjust dampening on shock to control the shock boing boing part of the ride?
Forks seem stiff to me also. Would your ATF oil be a better choice? thanks rj

[SpudRider]

Originally Posted by rjmorel

Spud, I've been wondering about my suspension and how to make it ride less harsh on the street. I weigh around 180 w riding gear and the pot holes on Walla Walla streets are bad. When I hit them sitting down it really rattles the old back bones. I have less then 100 miles on the RX3 so it's not broke in yet and I thought I'd wait 500-700 miles before doing any adjustments to change things.
On the rear shock is the preload changed by just turning the ring under the spring? Is there any set screw locking said ring? Any special tool used to turn ring?
I don't know squat about adjusting suspension like racers do but I'm assuming I want the least amount of preload so it's not as harsh and squats down more. Then adjust dampening on shock to control the shock boing boing part of the ride?
Forks seem stiff to me also. Would your ATF oil be a better choice? thanks rj

I just got done increasing the shock spring preload another three turns. I did take a few photographs. I'm going for a test ride, but I will post a thread later on this topic. The job is pretty easy, and the rewards are satisfying.

You certainly will enjoy the forks more if you replace the stock fish oil, about 2.5W, with real fork oil around 10W, or ATF. Check out the following thread. Later, I will add more information regarding the ATF I installed in my forks.

http://www.chinariders.net/showthrea...386#post184386

[G19Tony]

Originally Posted by SpudRider

I just got done increasing the shock spring preload another three turns. I did take a few photographs. I'm going for a test ride, but I will post a thread later on this topic. The job is pretty easy, and the rewards are satisfying.

You certainly will enjoy the forks more if you replace the stock fish oil, about 2.5W, with real fork oil around 10W, or ATF. Check out the following thread. Later, I will add more information regarding the ATF I installed in my forks.

http://www.chinariders.net/showthrea...386#post184386

I took your advice and got the Park Tool wrench on the way. I plan on doing the forks also.

[SpudRider]

I just completed another test ride after adjusting the shock spring preload on my bike. I have now recorded 1,135 miles on the odometer of my Zongshen RX3. Once again, the shock absorber performed significantly better with a larger spring preload. However, the shock response is still a little too soft for me. Therefore, I plan to tighten the spring preload yet another 3 turns. However, I am getting very close to the ideal setting.

[SpudRider]

Originally Posted by rjmorel

Spud, I've been wondering about my suspension and how to make it ride less harsh on the street. I weigh around 180 w riding gear and the pot holes on Walla Walla streets are bad. When I hit them sitting down it really rattles the old back bones...

Yes, the spring preload setting on the shock absorber produces a very harsh ride. Fortunately, adjusting the spring preload allows the shock to perform much better.

Originally Posted by rjmorel

On the rear shock is the preload changed by just turning the ring under the spring? Is there any set screw locking said ring? Any special tool used to turn ring?...

The locking ring for the shock spring has a single Allen bolt which tightens it. You adjust the spring preload either by turning the spring, or turning the locking ring, which sits above the spring at the top of the shock. You don't need a special tool to tighten the spring preload.

Originally Posted by rjmorel

...I don't know squat about adjusting suspension like racers do but I'm assuming I want the least amount of preload so it's not as harsh and squats down more. Then adjust dampening on shock to control the shock boing boing part of the ride?...

The spring preload on my shock was set to the mimimum amount. Therfore, I suspect your shock is the same, and you will want to increase the amount of spring preload to stiffen the shock response. The adjustable rebound damping of the shock works well, and is easy to adjust.

Originally Posted by rjmorel

Forks seem stiff to me also. Would your ATF oil be a better choice? thanks rj

The rebound damping of the forks is too soft, due to the low viscosity of the fork oil. I drained the stock fork oil, and installed Mobil1 Synthetic ATF, which has a viscosity of 10W. The thicker ATF allowed the forks to function significantly better.

[SpudRider]

Originally Posted by G19Tony

I took your advice and got the Park Tool wrench on the way. I plan on doing the forks also.

Good for you. For the new fork oil, I highly recommend Mobil1 Synthetic ATF, which is readily available at AutoZone, and many auto parts stores. ATF is excellent fork oil, and many of the "boutique fork oils" are either ATF, or hydraulic fluid. The two most important factors to consider when choosing a fork oil are viscosity, and the viscosity index (VI). The VI measures the ability of an oil to maintain its viscosity over a wide temperature range. Any fork oil with a VI over 100 will do an excellent job in a motorcycle fork, and all the ATFs I have examined have a VI which easily exceeds 100. Mobil1 Synthetic ATF has an excellent VI, and a viscosity equivalent to 10W fork oil.

[pete]

ATF has the same viscosity as 10W fork oil... but who's
fork oil.... 10w oil from one manifacture can be the same
as anothers 20w..
the number you should be looking at is the CST rating
of the fork oil...

there are weight & CST chats on the net..compare diffrent
brands you will be surpised....




.

[SpudRider]

Originally Posted by pete

ATF has the same viscosity as 10W fork oil... but who's
fork oil.... 10w oil from one manifacture can be the same
as anothers 20w..
the number you should be looking at is the CST rating
of the fork oil...

there are weight & CST chats on the net..compare diffrent
brands you will be surpised....

.

That is exactly correct. You need to check every manufacturer to see the actual viscosity of their fork oil. One company's 5W fork oil is another company's 10W fork oil.



Looking at Verdone's chart, I would estimate fork oil falls roughly into the following classifications.

2.5W is about 10 cSt viscosity
5W is about 16 cSt viscosity
7.5W is about 28 cSt viscosity
10W is about 36 cSt viscosity

Et cetera.

[SpudRider]

Looking at Peter Verdone's chart, you can quickly determine the 10W, 15W, oil weight designations from the sellers can't be trusted, since one vendor's 5W oil might have the same viscosity as another vendor's 10W oil.

http://www.peterverdone.com/wiki/ind...spension_Fluid

Also, one shouldn't completely trust the chart, either, since the viscosity of a particular brand of oil might change. The only sure way to determine viscosity is to read the product data sheet (PDS) or the manufacturer's safety data sheet (MSDS) for each individual oil. For example, the Verdone chart lists the viscosity of Mobil1 Synthetic ATF as 34.0 with a viscosity index (VI) of 199.00. However, the PDF for this ATF at the Mobil website lists the viscosity as 36.3, with a VI of 176.

http://www.mobil.com/USA-English/Lub...hetic_ATF.aspx

For the forks in my other motorcycles I have installed Valvoline MaxLife Dex/Merc ATF. I chose this fork oil for several reasons. First of all, it has the lowest viscosity of any ATF I have researched.

http://www.valvoline.com/pdf/maxlife_atf.pdf

As an added bonus, this ATF had the lowest price. I bought the Valvoline ATF for $13.50/gallon at my local AutoZone store. Contrast this price with the cost of the "boutique fork oils."

Last year I changed the fork oil in three motorcycles in one month, using the Valvoline MaxLife Dex/Merc ATF, and I still have over a quart of ATF left over. However, I did use Showa SS-7 Fork Oil for the inner cartridge of my CRF250X forks, since the valving is designed for an oil with a viscosity of 16 cSt.

Most of the Dexron VI ATFs also have a low viscosity around 30 cSt, which is very close to the Valvoline MaxLife Dex/Merc. However, none of them could match the price of the Valvoline.

I chose Mobil1 Synthetic ATF for the forks in the RX3 because it has a higher viscosity than the Valvoline MaxLife Dex/Merc ATF. I wanted a higher viscosity of 10W for the RX3 forks, instead of the 7.5W provided by the MaxLife Dex/Merc ATF.

[SpudRider]

I have posted a tutorial thread which describes how to adjust the spring preload of the shock absorber for the Zongshen RX3. The thread is located at the following link.

http://www.chinariders.net/showthrea...d=1#post184432

I have added a link to this thread under the Maintenance subheading in the Zongshen RX3 Sticky Thread, which is permanently pinned to the top of this forum.

http://www.chinariders.net/showthread.php?t=14228

[jjn]

I remember looking through some information on this bike. It seems it uses two oil filters. One on each side? That's a bit strange. Is this correct?

[G19Tony]

Originally Posted by SpudRider

Good for you. For the new fork oil, I highly recommend Mobil1 Synthetic ATF, which is readily available at AutoZone, and many auto parts stores. ATF is excellent fork oil, and many of the "boutique fork oils" are either ATF, or hydraulic fluid. The two most important factors to consider when choosing a fork oil are viscosity, and the viscosity index (VI). The VI measures the ability of an oil to maintain its viscosity over a wide temperature range. Any fork oil with a VI over 100 will do an excellent job in a motorcycle fork, and all the ATFs I have examined have a VI which easily exceeds 100. Mobil1 Synthetic ATF has an excellent VI, and a viscosity equivalent to 10W fork oil.

Thanks for all the research you do Spud. I will try the ATF you recommend. Your information makes these bikes easier to work on. I wonder if MIL SPEC HYD 83282 would work. If it's good enough for fighter jets, it should work for us! It makes sense to use hyd fluid in a hyd component.

[G19Tony]

Originally Posted by jjn

I remember looking through some information on this bike. It seems it uses two oil filters. One on each side? That's a bit strange. Is this correct?

It uses two filters. They are both on the same side.