If you look at the first picture, you may notice that the saddle post is coming out of the frame at a slightly wrong angle.

Side note: Yes, this bike a size or two too small for me.

BUT, and here's my point, it seems stable. And it does give a little more length to the bike, which is welcome.

So yeah, just wanted to check if this is a common problem or not. I'm also worried it might get slowly worse over time, but I don't know, might be just result of a bad bump.

NO

It is not moving at the moment - that's not the same as stable.

No, it's not common in general, but quite common when the seat post is both extended too far and inserted too little.

No way for us (or you) to know if it will get slowly worse or will fail without sufficient warning to avoid injury. I believe those dotted lines are what's known in the biz as "minimum insertion" - probably say that on the back of the post below the marks. You should not see them when the post is mounted in the bike.



Replace it, guaranteed less cost than a hospital bill.

Oh wow, that's a good tip. (thanks for the quick response btw)

I was just thinking of prolonging the purchase of a new post. I think I've changed my mind now, that post was inserted waaay beyond that tiny dotted line (the surface was scratched so I didn't see it).

Plus, you know, It must be quite nasty going 30 kmph and then finding that the surface you're sitting on is suddenly lowering.

You're welcome. You will need the seat post diameter. It is sometimes inscribed on the post but in that condition possibly not visible. If not then you need a vernier caliper or similar. Measure in mm, most sizes are even decimals - 26.8, 27.2, etc. Once you have that, measure the length in mm to where you had it set, add about 100mm. Google (XXmm) long seat post or check with LBS.

THat post looks way too short for its intended use. You can get longer ones though and I would strongly recommend one.

Agreed with everything said above, that is a big NO.

I feel a picture speaks a thousand words.

Haha, now I see why the "newbie" right below my username is coloured bright red. Checking this with the forum was definitely a good choice.

As for the post, the diameter is 27.2 mm. Length from the end of the tube until the min. insertion point is ~180 mm.

I'll check a LBS first thing tomorrow. Hoping to get one around 350 mm for not much more than 30€. I guess I'll just have to see from there, none of the stores really properly display all of their products, just the bikes at best.

What I would do is measure the amount of exposed seat tube after you have the saddle where you want it. Then just make sure that any new post you get has at least that much post showing before the insertion marks.

PS: the tip of the seatpost was actually so bent, I couldn't even push it far enough into the required minimum insertion zone.

Yep.

That's another good tip.

Well, actually, the seat was not where I wanted it. It was way over the min insertion point and my legs were still a little uncomfortable (again, it's an old bike that's too small for me).

I'll just remember that the current one had 180 mm tube and 100 mm beyond min insertion point. So if the new one's roughly 300 mm with 100 mm beyond insertion point, I should be totally fine.

But then again yeah, maybe longer posts require longer insertion points, I don't know. I'll definitely check everything in the shop before buying.

no
that bike is 3 or 4 sizes to small for you

the correct solution is to sell it and buy something that fits

I absolutely agree, and I would love to buy a new bike, but it's tough to pay 250-400€ for something, when you don't have a job... or well can't have job.

My parents bought me this bike when I was around 10-11, I think. Now I'm 15, so there's the problem . I guess puberty and those darned growth hormones are to blame!

But anyway, if we're allowed to drift from the original topic, how much do you think the bike would really be worth?

I mean, small Merida Kalahari 510, brakes are squealing slightly (can probably be fixed), derailleur works too, but is poorly adjusted, could really use a proper setup. 120€ would be generous, no?

OK, this just a thought. Buying a new post still more reasonable.

PS: I do have the option of using a pretty cool Trek road bike. Bigger, more comfortable. It's not mine, different story, so not a permanent solution by any means.

So yeah, just wanted to mention that I'm not completely bikeless and in a hurry right now. I can give this a bit more thought. Thanks for all the advice!

450 mm is a common length for long seat posts. Using that length and the diameter in a search wiill yield plenty of options. If you are still determined to get a new one for this bike I'd go for that length, but mount the seat as far forward as you can.

Thanks.

But why forward? If the bike's small, shouldn't the seat be more backward to give additional length?

Very interesting.

that is the price for a new bike
a second hand bike could be much less

also
seat height is only one aspect of bike fit
if you get a longer post you will still have a very poor fitting bike
with the saddle much higher than the handlebars
and the reach from the bars to the saddle much too short


ps
maybe your parents will let you get a job
to pay to have the orange carpet replaced
where you left a big grease stain on it
when you laid the seatpost on it
to take picture number two

Nothing is going to make that bike fit decently. I'm more concerned about the cantilever effect of that long a post plus a seat mounted too far back. Nobody is going to be able to tell you the value of your bike except someone who buys it, but certainly if it needs several adjustments it's not worth a lot. On the other hand the cost of a different bike is only its cost minus what you can get for that one. I'd consider looking for a good used bike. A co-op or community bike shop might be a good source for such an item as well. You could just cut off the bent part of the seat post to make is useable for someone else.

Couldn't agree more, You'll be able to get a bike for a very reasonable price which will serve your purposes well. There is no point spending money on parts for a bike that isn't going to be of any use to you. You are better of saving up money by doing job/chores etc. than sinking your money into this bike.

Gah, darn it. :/

You're right, didn't think about that.

Handling would still be a bit twitchy, legs would probably be better but lower back would get cramped quicker. Hmmmm.


Used bike sounds better now. But yeah, too many variables, will look further into this, can't say anything right now.

I guess I'm not buying anything right now, Wohoo! Thanks for all the great help!

I was thinking about what you said when it comes to selling the bike.

I mean, I could probably get the gears and breaks into decent shape, but if the original seatpost won't even go back in all the way then it's for nothing.

Bending that thing into shape will be interesting if I do get to selling it. Of course I wouldn't sell it without mentioning it.

You should be able to find a replacement seat post really cheap at a bike shop if the have old ones or at a bike cooperative. Just make sure you get the applicable size.

As I said you can just cut off the bent portion at the bottom, but 27.2 is a fairly common size, so a used one is an option. Use your imagination a bit!

Yes, sorry, I promise I will.