[Conley]

RE: Need help with a rear shock on a '98 litespeed Unicoi (YBB)

Everyone,

I just bought a '98 Litespeed Unicoi off of Ebay for my wife, because she wanted a MTB with a softer ride. I am now in the process of rebuilding it. When I took apart the rear shock, I was expecting to see a Moots style YBB design. But, that is not what I found. I did not see (https://moots.com/wp-content/uploads/TECHpaper_YBBshock.pdf) the spring or the urethane bumper inside the spring, or even the Black Plastic Spacer.

Instead of these parts, I found a robust, 4-inch long by 7/8-in diameter aluminum pipe with a wall thickness of approximate 3/16-inch.

Does anyone know if this is correct? Or, did someone try and convert this bike to a hard-tail mountain bike?

I called Litespeed. They said that they don't support it anymore. I called Moots, and they said that they don't know anything about it, and therefore could not help me.

If this is supposed to look like a Moots, does anyone have some dimension on the plastic spacer, spring and urethane bumper that Litespeed used? I would really appreciate it so I can look for replacement parts.

Or if someone know someone who makes a conversion kit to a Moots style YBB. I would really appreciate that information, since they do support their bikes.

Thanks in advance,
David

 

[NZPeterG]

Try phoning up Lynskey titanium bikes.
As they started Litespeed and still owned it in the late 1990's before selling it off.
Good luck

Sent from my SM-G960F using Tapatalk

 

[Conley]

Everyone,

Sorry for the delay in response, but work happens.

Looking at replacing the titanium Slider Assembly: The measurements for the titanium tube are 1-inch OD, by 3 3/8-inch long with a wall thickness of 18 gauge (OD=25.4mm, ID=22.86mm, Len=102mm). I ordered a piece of titanium tubing off of ebay with the following dimensions OD=25mm, ID=22mm, length 350mm. I am still waiting on delivery. I am not sure how smooth or rough the tubing will be, but I have some woodworking equipment that I can use to polish it and a hacksaw to size it.

I don’t have a clue on finding a replacement spring. So, I order off of ebay a Chinese RED “TM” medium load and a GREEN “TN” heavy load compression springs that were OD 22mm, ID 11mm, Length 100mm. I am hoping these will fit inside the 22mm ID of the Titanium tube. The worst case is If a little grinding does not get it to work, I can reorder OD 20mm springs.

I will report back after I get the parts and give the bike a test ride.

Thanks,
David

 

[Conley]

Everyone,

Yesterday, I received the load compression springs and titanium tube.

As expected, the OD of the new titanium tube has a slightly smaller OD (25.4 vs. 25mm). The exterior surface would take some time to polish to make it as smooth as the original tube. However, the original tube does have some noticeable wear, which is why I ordered the new tube.

The springs will fit inside both tubes without binding. I installed the lighter Red “TM” spring. I think it is too light, but my 125lb wife thinks it is perfect. Since the harshest paths she will be riding are rails to trails and paved surfaces. I am okay with leaving in the red spring. BUT, I am going to order a the brown “TB” Extra Heavy Load spring.

Since the nylon bushing inside the upper seat stay tube was sized for the 1-inch OD titanium tube, I decided to reuse the original titanium tube. If I every replace the titanium tube in the future, I will buy another titanium tube with the proper 1-inch OD because of the nylon bushing.

Time to go riding!

Thanks,
David

 

[Conley]

The red spring (Medium Load) was not strong enough. She rode over a speed bump and the rear shock bottomed out.

I installed the Green Spring (Heavy Load) tonight and will have her test it tomorrow. I also found, and ordered a Brown Spring (Extra Heavy Load) off of eBay tonight. Last time it took 3 weeks to receive it.

 

[Conley]

We went for a test ride yesterday and my wife never bottomed out using the Green Spring (Heavy Load), even on the speed bumps.

I rode it a few hundred feet to dial in the rear derailleur. I was bottoming out on just about every pedal stroke. I weigh about twice as much as my wife. So, I would say that if you weigh over say, 160 lbs, I would use the Extra Heavy Load spring.

Tip for installing these YBB type suspension: Add a little preload when installing. I used a clamp to help hold a little pressure on the spring as I clamped the monostay binder. This keeps some tension on the spring at all times. Otherwise, you get a little annoying sound as the spring and frame make contact with each other.

The springs that I have been ordering and using are standardize JIS spring.
I think the original springs (based on the spring colors: Red is Heavy and Yellow is extra Heavy) use standardize ISO springs.

I hope this helps someone else.

 

[adam34]

David, thanks for posting all of this last year. I have a 1998 Litespeed Unicoi that I am planning to attempt to rebuild the rear shock just as you did (I will likely re-use the titanium slider). I am curious if the springs you ordered off Ebay have held up well? I am around 200lbs so seems like it's definitely worth getting the brown extra heavy duty spring? Also curious if you have any other tips to the process of changing out the spring? Thanks!

Adam