Issues with my bike

[dimitrin]

I am hoping someone has some insight on a couple issues I have with my bike.
1st is the the seat tube/OneUp dropper post. It is extremely difficult to insert the dropper post more than halfway into the seat tube, and when fully inserted the dropper will not extend after being fully dropped.
2nd is that the mileage displayed in the app under "bike details" is completely inaccurate. In fact I beleive it is actually doubling the mileage of each ride.
Has anyone else encountered either of these issues?

 

[Streddaz]

I am hoping someone has some insight on a couple issues I have with my bike.
1st is the the seat tube. I have a OneUp dropper that seems to bind in the seat tube when fully inserted. It severely restricts the operation of the post.
2nd is that the mileage displayed in the app under "bike details" is completely inaccurate. In fact I beleive it is actually doubling the mileage of each ride.
Has anyone else encountered either of these issues?

For starters, what bike do you have? Model? Motor? Year?

When you mean "fully inserted"? Do you mean sliding the whole post assembly into the frame or do you mean when you actuate the dropper post and compress it?

 

[goroncy]

I am hoping someone has some insight on a couple issues I have with my bike.
1st is the the seat tube. I have a OneUp dropper that seems to bind in the seat tube when fully inserted. It severely restricts the operation of the post.
2nd is that the mileage displayed in the app under "bike details" is completely inaccurate. In fact I beleive it is actually doubling the mileage of each ride.
Has anyone else encountered either of these issues?

With OneUp I can help you with. By saying get rid of it. We have the same issue. I don't think that anything can be done with it because OneUp is not really a dropper seat post. It's just an office chair cartridge enclosed in something like a saddle post. Because it is a cartridge it cannot be serviced or altered. If you want to have something "real" buy KS, Fox, Vecnum. Stay away from OneUp, PNW, Giant, ... (all cartridge/disposable designs which are wallet and environment unfriendly). As the last resort try to pump it more. Maybe it will help to "unstuck" it.

 

[Tony4wd]

You could try something simple - unscrew the "mid cap assembly" (#8 in the link), apply some light grease, screw it back together and see how it goes.

DROPPER POST V2 CLEAN & GREASE SERVICE

Tools needed Waterproof grease (ie. Slickoleum, Slick Honey) Rubbing alcohol 2 & 5mm hex Pick tool Needle nose pliers Strap wrench 14 mm or 17mm wrench (or adjustable wrench) Lint-free Cloth COMPLETE EXPLODED VIEW & PARTS LIST This service should be completed every 50-100hrs of riding depending...

can.oneupcomponents.com

 

[ilostmypassword]

I have a oneup dropper and they are prone to sticking if the seat clamp bolt is to tight. Try slacking that off a little and see if it fixes it. For the record I love this post and it's a good performer. Does need lubing from time to time though and an easy job.

 

[LJR69]

For the mileage issue, check that the wheel size is set correctly in the app for your rear wheel. If it's set to automatic then you maybe better off measuring it with the tyre inflated and entering it manually (which I've had to do for one for my bikes before). Also if you've installed a speed de-restrictor then some models of those will screw up mileage (and speed) displays.

 

[dimitrin]

Wow, thank you all very much for all of the replies!
Apologies for not clarifying, it is a 2023 giant reign e+ size medium, no de-restriction devices but it does have all of the most recent updates applied.
I have two other OneUp dropper posts in 2 enduro pedal bikes that I've had for several years, they operate super slick and are very quick to actuate. I've already greased and re-greased under the top cap and also made sure the pressures were max (300psi) on the post.
The torque spec from Giant and OneUp is for 4 Newton meters on the seat post clamp I am only running 3 Newton meters.
I suspect that there is some interference occurring inside the seat tube where all of the welds come together from the top tube, the linkage mounts, etc, which a properly sized ball hone would likely remedy.
Either that or the seat tube or seat post itself has a irregularity such as a slight bend or swollenness along it's length.
I guess what I'm really asking with regards to the seat post issue, is if anyone has had issues utilizing the full insertion depth of the seat tube with a post?
I will familiarize myself better with the app to locate the area where I can input the tire diameter, that makes sense that it could be not set correctly.
Thanks again, and I'll be sure to reply with any remedies we figure out.

 

[irie]

...
I have two other OneUp dropper posts in 2 enduro pedal bikes that I've had for several years, they operate super slick and are very quick to actuate.

To narrow things down install a OneUp dropper post from one of the 2 enduro bikes and see how it works.

 

[emtbPhil]

Every dropper post I've seen when bike servicing that sticks has been down to the seatpost clamp being too tight crushing the dropper tube.

Loosen it off so it's barely at the point of stopping it moving, see if the problem persists. If it doesn't then tighten back up with a torque wrench to the correct torque

 

[dimitrin]

Thank you for the replies.
As i mentioned earlier the spec for the torque of the clamp is 4nm by both Giant and OneUp. I have the clamp set to 3nm.
When the seat post is fully inserted it sticks whether or not the clamp is even on the bike, if I pull it halfway out it works much better, which is why I suspect it's either the tube or the post.

 

[Streddaz]

Thank you for the replies.
As i mentioned earlier the spec for the torque of the clamp is 4nm by both Giant and OneUp. I have the clamp set to 3nm.
When the seat post is fully inserted it sticks whether or not the clamp is even on the bike, if I pull it halfway out it works much better, which is why I suspect it's either the tube or the post.

I think you may be right in regards to the post. You could totally rule it out by trying another post if you had one at hand. Some frames are notorious for having clearance issues in areas where tubes join.
You could ream the seat post but it may be difficult to find a place that has a correct size reamer.

 

[dimitrin]

I do not have another post of the correct length. Fortunately I have located a reamer and also a hone of the correct size, just waiting for the opportunity now.
From what I understand it's best to do the reaming and honing with the frame upside down so all the particles fall out of the tube rather than deep into it, that part is going take some figuring.

 

[emtbPhil]

Thank you for the replies.
As i mentioned earlier the spec for the torque of the clamp is 4nm by both Giant and OneUp. I have the clamp set to 3nm.
When the seat post is fully inserted it sticks whether or not the clamp is even on the bike, if I pull it halfway out it works much better, which is why I suspect it's either the tube or the post.

Sorry was late and I completely missed that you'd already tried that
Does sound like maybe the tube is oval'd or there's something in there pinching the post.

The only other thing I've seen is the dropper cable all kinked up when the post is inserted which prevents it fully pulling the release leaver. As you lower the post into the frame you're supposed to gently guide the cable out too but a lot of people seem to connect the cable then just jam the post down and kink the cable

 

[Nomad1]

With OneUp I can help you with. By saying get rid of it. We have the same issue. I don't think that anything can be done with it because OneUp is not really a dropper seat post. It's just an office chair cartridge enclosed in something like a saddle post. Because it is a cartridge it cannot be serviced or altered. If you want to have something "real" buy KS, Fox, Vecnum. Stay away from OneUp, PNW, Giant, ... (all cartridge/disposable designs which are wallet and environment unfriendly). As the last resort try to pump it more. Maybe it will help to "unstuck" it.

huh that certainly has not been my experience with oneup. At any rate setting the proper pressure and cleaning the shaft and apply something like Stanchion lube on the regular is what you should do with any dropper post. Also Oneup has a 2 year warranty.

 

[dimitrin]

It looks like we will be able to check out the situation with the reamer this weekend.
Looking at that down tube, the section where it is welded with the top tube and the beefed up area where the rocker linkage attaches are right about where you can feel significant increased friction when inserting the post.
And if I pull the post out to where less of the post is inserted into that welded area/beefed up area it operates much smoother.
We are careful to insert or rectract cable housing as we insert or pull out the post.
I'm much more confident at this point we'll have it figured out as to whether it is the seat tube or the seat post causing the issue.
Unfortunately, since I've got the bike, it's been in the shop far more than I've had it at my house due to this situation. Otherwise it was totally rad the 3 days I got to ride it.

 

[Nomad1]

WAIT you didn't by chance cut you cable housing to long so when you incert your dropper it push up against it. when you install your dropper try hooking it up and just setting in and pulling on the cable & housing to pull into the tube.

 

[RustyIron]

1st is the the seat tube. I have a OneUp dropper that seems to bind in the seat tube when fully inserted. It severely restricts the operation of the post

There's a mechanical contraption at the bottom of the seatpost. If you insert it too far, the actuator can be binding up, or the cable could be getting kinked. You might have to pull the seatpost out to confirm that nothing's been bent.

2nd is that the mileage displayed in the app under "bike details" is completely inaccurate. In fact I beleive it is actually doubling the mileage of each ride.

How's the speed indication look? Could it be set for kilometers and you're expecting miles?

 

[dimitrin]

There's a mechanical contraption at the bottom of the seatpost. If you insert it too far, the actuator can be binding up, or the cable could be getting kinked. You might have to pull the seatpost out to confirm that nothing's been bent.


How's the speed indication look? Could it be set for kilometers and you're expecting miles?

Fortunately this has been triple checked and is not an issue

 

[dimitrin]

I have triple and quadruple checked housing and cable length, torque of the seat tube clamp, insertion depth clearance, air psi, stanchion lube and cable interference under the battery with the mechanics at the shop. None of which are responsible for this particular issue.
Now we did notice an area of the dropper cable housing that was abraided upon, we assume by the battery, but upon the numerous times we have removed the post it is not interfering with the actuation of the cable, it slides in the housing without issue.
Only when the post is inserted more than halfway in does it interfere with the function of the post.

 

[Evelhornet]

Sorry was late and I completely missed that you'd already tried that
Does sound like maybe the tube is oval'd or there's something in there pinching the post.

The only other thing I've seen is the dropper cable all kinked up when the post is inserted which prevents it fully pulling the release leaver. As you lower the post into the frame you're supposed to gently guide the cable out too but a lot of people seem to connect the cable then just jam the post down and kink the cable

I think this is most likely the issue!

 

[dimitrin]

You think that is most likely the issue even though I have clarified that the cable slides in the housing without issue and that we have triple checked that the cable is not kinked?

 

[G-Sport]

With OneUp I can help you with. By saying get rid of it. We have the same issue. I don't think that anything can be done with it because OneUp is not really a dropper seat post. It's just an office chair cartridge enclosed in something like a saddle post. Because it is a cartridge it cannot be serviced or altered. If you want to have something "real" buy KS, Fox, Vecnum. Stay away from OneUp, PNW, Giant, ... (all cartridge/disposable designs which are wallet and environment unfriendly). As the last resort try to pump it more. Maybe it will help to "unstuck" it.

You can actually service and repair these cartridges. It's pretty easy. I am sure they would rather you just buy a new one but they can be opened with 90degree circlip pliers.
I've also been very happy with mine, got two that have never needed attention, the only one I have opened is a friend's that seems to repeatedly chew up the small o-ring at the top of the push rod that closes the bypass.

 

[Nomad1]

How long is the dropper? Did you ream out the tube yet? Think twice before you do because if the tube is not just a little out of spec you could compromising its strength at key location. This may not be the case at all but should certainly be considered.

 

[dimitrin]

Thanks, yes I have considered that it will be be just the slightest amout out of true as I can currently insert the post completely, but after about halfway it requires all my effort and some twisting as well. The same for removing it... but it will go in.
Looks like we're going to do it Tuesday, I also have a ball hone and may decide that's all we need to use.
I want to ride it Wednesday so I sure hope we get it figured out Tuesday!

 

[G-Sport]

Does it work ok if you insert it less deeply into the frame?
My thinking is that the seat tube might be a little bent and is forcing a bend into the dropper.
IF it is OK when raised up 40mm or so then you could consider taking material off the bottom of the dropper rather than out of the frame
The one-up droppers have a reduced diameter part just before the base and then a final section at full diameter. Taking 0.2mm or so off this last section might fix the issue without risking voiding the warranty.
Frames with this suspension layout can be prone to failure at the seat tube pivot as it is so you don't want to be refused warranty if it breaks here.

 

[dimitrin]

Giant sent us the reamer

 

[dimitrin]

Thank you, I'll be careful.

 

[Nomad1]

There is one thing that leads me to believe that it still it could be the cable housing because you aren't able to pull the dropper in to the tube by the cable and housing to make sure the cable housing isn't to close to the actuator. because I can't see you being able to check that unless you can pull the motor and look right up to the bottom of the dropper.

 

[Nomad1]

Were you able to figure out what the issue was?

 

[dimitrin]

There is one thing that leads me to believe that it still it could be the cable housing because you aren't able to pull the dropper in to the tube by the cable and housing to make sure the cable housing isn't to close to the actuator. because I can't see you being able to check that unless you can pull the motor and look right up to the bottom of the dropper.

Yep, the shop that built the bike had the cable housing kinked up pretty bad inside the seat tube each time they slide it in. In fact the outer (black) portion of the cable housing was completely skinned off in sections, I dont think they were aware that the battery needs to be removed when sliding the cable housing in or out on that bike.
Pulled the battery and the motor to learn what was scrapping the housing up so bad. The cable routing over the motor on that bike has a few very sharp edges that are prone to hang up and scrap the cable housing. Also very congested with wire harnesses. The mechanic that figured it out arranged the harnesses to improve the routing and added a outer sheath to the housing where it passes over the motor to protect it and help it slide a little better.
The main thing will be to ensure that anyone that pulls the dropper post removes the battery first and feeds the cable housing from the battery compartment.