Haibike seat tube sizing?

[TooMuchWitt]

This was user error - I bought a Kinekt suspension seatpost and it worked out perfectly.

 

[BlackHand]

It looks like you got the mid-step version? Which frame size? How long is the seatpost?

Just for comparison: I have a Trekking 9.0 S high-step 52cm (medium) . My seatpost is 400mm long and can insert to about 290mm. The equivalent frame in the mid-step is a 48cm. If they ship all bikes (both frame styles) with the same seatpost I would expect it to insert to about 250mm.

 

[rich c]

Thinking they do that so you don't send the tube all the way in to avoid wires going through the frame. Trying to remember if my tail light wire goes through there? But mine are 2016 models.

 

[batmick1]

Could be intentional, to prevent you from moving the post too deep and into the bend, which might damage the frame.

 

[rich c]

Could be intentional, to prevent you from moving the post too deep and into the bend, which might damage the frame.

Good point. Not sure it would damage the frame, but could get wedged in if it slipped and the rider weight jammed it into the curve. So with that curve, you wouldn't get much more depth anyway. Cut a little off the bottom of the seat tube if you need that.

 

[J.R.]

I've read of bikes with a seat tube with a bend that didn't have a stop and the post got stuck and the owner used a pipe wrench to remove the post. Destroyed the post and damaged the frame. The stop wouldn't have to be pretty inside to work. I think I'd like the stop if my seat tube had a bend.

 

[BlackHand]

TBH, your pic looks more or less the same as what I see in my tube. Mine has a small lip also that only goes about 1/2 way around the inside surface roughly 1" up from the bend. FYI, My seat tube is approx 320mm down to the bend.

Maybe @TMH will weigh in? They have a couple Trekking 7.0 ebikes and I think at least 1 is a lo-step.

 

[TMH]

TBH, your pic looks more or less the same as what I see in my tube. Mine has a small lip also that only goes about 1/2 way around the inside surface roughly 1" up from the bend. FYI, My seat tube is approx 320mm down to the bend.

Maybe @TMH will weigh in? They have a couple Trekking 7.0 ebikes and I think at least 1 is a lo-step.

No, both of our '19 Trekking 7.0's are high step diamond frames.

A couple of pics - the first showing the full length of my seatpost (XL frame size) and the second showing how far that seatpost fits into the seat tube.

I also tried to take a photo of the interior of my seat tube, but wasn't really successful (you did a good job at that!) I also see something impinging on the I.D. of the seat tube, but maybe it is lower down on my frame (or the fact that I am tall so I need my seat post up higher).

Not at all as much impingement as on your frame, but as discussed mine is a different frame style.

I have several bikes where the seat tube stops full insertion of the seat post, and this comes into play on my wife's bikes as she is only 5'6" tall. In some cases I have had to use a pipe cutter to shorten the seat posts on her bikes. (And if you do this don't forget to mark a new line for the 'min insertion' which is higher by the same amount you cut off - for safety's sake in the future).

I would try to find out through the folks at Haibike USA whether this is intended on your bike frame size and style, or whether it is something unintended which happened during manufacturing. It may take longer for them to get back to you, but it seems to me that they would have more knowledge about a situation like this than any dealer (unless you can find a dealer who has already seen this and already contacted Haibike in the past).

Good luck - it should be a really sweet bike when you get it up and running to your needs.

 

[BlackHand]

Thanks TMH!

Yeah, my biggest takeaway from this thread is that TooMuchWitt's seat tube photography skills put mine to shame.

 

[Mike TowpathTraveler]

I can't imagine why you need to go so far down in that seat tube unless the frame you bought is just too big for you.

I thought I read years back that Haibike hydroformed all of their tubes. If you think about it, having the lower third of that seat tube at double or triple the wall thickness is sound engineering; considering the motor's special dies cast frame mount is welded up to that lower end of the seat post. As well on their dual suspension frames, there is substantial supporting exterior pieces that are welded up to that seat post.

Such good engineering the frame is, I seem to recall only one person reporting of a cracked frame on this seat tube, down low; I believe on this forum, but it's been quite a few years ago. And we don't really know what kind of abuse that person subjected that frame to.

I have a 2016 Haibike Full FatSix. It appears that alot of the individual frame components are closely matched to each other; ie, your Trekking seat tube might also fit a hard tail mtb Haibike, so close in family appearance they are. Many Haibike mtb's have a hole cut on the lower third of the seat tube to accomodate a dropper seat post cable.

Maybe a bike shop owner can chime in and assist you here or you could take your bike to an LBS and talk to them about your concerns. Myself, I'd trim a bit off the seat post till you got your best, most comfortable fit.

Nice bike, btw!

 

[J.R.]

I sure hope that I got the right frame size! I bought the step-thru 52cm frame, and I'm 5'11".

As it is, I probably only need to take 2 inches off the post, so it's not the end of the world.

Unfortunately, the seat tube being so long (relative to other bikes with similar geometry) makes it so I'm going to be just-shy of the clearance needed for a suspension seatpost. That sucks cuz I was looking forward to getting one.

I think the Kinekt is the lowest out of the popular ones (can't use Suntour or ShockStop due to having the preload adjustment on the bottom of the 350mm post)

If anyone has the kinekt, what is the lowest clearance that would work for it?

I'll do a full write up in the Haibike forum!
Just pumped up the tires and took it on a ride around my parking garage - everything seems to be in order. The motor has a slightly higher-pitched whine than the one I demoed, but that's likely due to being brand new.

Maybe your setting your saddle too low. Are you trying to setup the bike so you can rest your foot on the ground from a sitting position? That wouldn't be the best thing to do with a trekking style bike. It's not good for your knees, hips or back and you won't have a proper pedal stroke. You'll have less power. There are crank forward, flat foot bikes designed for that style of riding. Properly set most people can barely touch the tip of their toes with one foot. If that. You really need to leave the saddle to put your feet down. A 52cm frame should work for most 5'-11" riders, unless you have a short inseam.

 

[rich c]

Seat tubes don't get "hollowed out". It's tubing. These pics are my 2016 Haibike XDURO Trekking S RX. There looks like a tab inside my tube, 10.5" down from the top.

 

[BlackHand]

Yeah, looks like it's entirely possible I went one size too big on my frame lol. Haibike sizing is weird......
Actually, it's possible I'm just used to too-small frames and seat heights, and it's something that I'm going to have to get used to.

FWIW I felt the same way at first. It's just so much more bike than the Rockhopper I was using. I'm riding now with the seat almost 1 1/2 inches higher from where I started just as my comfort and confidence have grown. Take your time, and don't be afraid to tweak.​

 

[Ravi Kempaiah]

I bought the step-thru 52cm frame, and I'm 5'11".

That is the right frame size. I am 6ft and I had a 52cm - step over frame and I never had to push the seatpost down.
If you need to go all the way down, then I suspect you not getting the bike fit right. When you are fully seated on the bike, your toes should barely touch the ground.

 

[BlackHand]

Kinekt says 4" is good.

25% off at Selle Anatomica looks like it is still up.

 

[TMH]

Yeah, so as it stands, the "max insert" setting is about 1" too high. It will fit me if I change the exposed seatpost from 5.5" to 4.5", so I just need to cut off part of the seatpost to make that happen.

Ravi, do you happen to know if 4.5" is enough for a kinekt? Or should I just be happy with it as-is? lol

Looks like 4.5" will be about the minimum "exposed height" you would need for a Kinekt.

 

[BarryS]

Yeah, so as it stands, the "max insert" setting is about 1" too high. It will fit me if I change the exposed seatpost from 5.5" to 4.5", so I just need to cut off part of the seatpost to make that happen.

Ravi, do you happen to know if 4.5" is enough for a kinekt? Or should I just be happy with it as-is? lol

I would not cut a seat Tube before going to a Bike Shop and making sure your Frame size is correct : I am between 5'11-6'0 : My frame is 58CM : Maybe the sizing is different : Go get a fitting

 

[TMH]

The prevailing thought, based on what I have read, is that the Haibike Trekking frames 'run large'.

Didn't really seem the case to me as I am very comfortable on my XL sized frame, and its nice as I don't have to run the seat post way up like on many other bikes (I'm 6'4" with a 33" inseam).

My wife is 5'6" tall and I originally ordered a small (48 cm) high step frame for her. But that order didn't go through as the last bike had been purchased before me and the company's inventory didn't update quickly enough. Tried next for a low step model, but those also ended being sold out.

So I measured frames on her current bikes, especially the stand-over height. With those measurements I found that the high step medium (52 cm) should fit her, bought one and she loves it.

I will say that she is a very confident and capable rider, and is used to leaning her frame over (muscle memory) when she comes to a stop and puts her foot down. Perhaps this allows her to be more comfortable on a bike which others may feel is too tall for them?

At 5'11" I would really think that your 52 cm frame size is appropriate for you (@Ravi agrees - and he is a very knowledgeable resource). Unless you have unusually short legs. As @BlackHand said above, it just may take a few rides on your new bike to find that the size actually works very well for you, and it precludes you from the hassle and expense of returning it.

I'm rather tall so my opinion may be biased by that, but my preference has always been one size too large is preferable to one size too small in bikes.

 

[TMH]

For what it is worth, I know that you were asking about a Kinekt seat post but I have found with the ride of our Trekking bikes (due to the way they are built and the larger volume tires, front suspension fork, etc.), the ride is very comfortable without a suspension seat post. I really like the OEM seats on the 7.0's, but don't know whether the same seat is provided on the 4.0's.

I'm glad that you are bonding with your new bike!

 

[TMH]

Proper saddle position (height) means that you get full leg extension at the bottom of your pedal stroke (without hyper-extending). Generally one does initial set-up by raising the seat to the height of their hip while standing next to the upright bike. Then fine-tuning happens after riding a bit.

'Proper' saddle height is most important on acoustic bikes, as it allows the rider to provide maximum efficiency during the pedal stroke. Definitely not as important on an e-bike where you have the nice motor assist. If your seat height is too low, it will feel like your knees are going to come up and hit you on your cheek bones while pedaling.

To summarize, since saddle height is not as critical on e-bikes, make it comfortable for you, and don't care about what anyone else thinks!