[Closed] frankenbikes with long seatposts

Thats got frame failure written all over it...

I'd say on the weld where the lower half of the top tube joins the seatpost 🙂

Is there about 20mm of post in the frame or have you got the only 500mm Reverb in the world?

Nothing wrong with a long seat post if that works for you. But as above are you sure that Reverb is correctly fitted?

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/thread closed 😉

this was my last bike before the parts got transferred to my current one...the frame got pinched from my shed along with my DH bike by some scrote(s) last year....
the seat post is the same as the one on wwaswas's bike and had plenty more left in the frame...

[url= http://i919.photobucket.com/albums/ad37/gonzy1/540342_3929449878445_170560153_n1.jp g" target="_blank">http://i919.photobucket.com/albums/ad37/gonzy1/540342_3929449878445_170560153_n1.jp g"/> [/img][/url]

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🙂 The reverb is fitted 10mm past the min insert line so no problems there, dinny worry lads. It's just to ride a medium at 6ft in a good efficient pedalling position that's what happens! (and I don't want a large, I can't get used to how they feel).

The term "Frankenbike" is reserved for the creatively special.

wwaswas is that actually your bike or an internet pick?

(and I don't want a large, I can't get used to how they feel).

You are Hora and icmfp

[i]wwaswas is that actually your bike or an internet pick? [/i]

my actual bike.

although it was posed for the photo with only a couple of cm of post in the seat tube.

I ride it at about this height which is far too sensible...

[URL= http://i239.photobucket.com/albums/ff167/LukeBurstow/072_zpsdff16bab.jp g" target="_blank">http://i239.photobucket.com/albums/ff167/LukeBurstow/072_zpsdff16bab.jp g"/> [/IMG][/URL]

glasgowdan - looks horrendous, must ride odd, maybe get a bike that actually fits you?

gonzy - hopefully you replaced it with something that looks less like a Halfords 'my first bike'?

meoooow

The reverb is fitted 10mm past the min insert line so no problems there, dinny worry lads

That's the minimum insertion mark on the reverb? not the recommended minimum insertion on the frame? (normally mentioned in the in manual) they are not the same thing....

Another Black-Spire post.

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Frame is cracked exactly where you would expect.

hopefully you replaced it with something that looks less like a Halfords 'my first bike'?

does this appease your eyes?
[url= https://fbcdn-sphotos-h-a.akamaihd.net/hphotos-ak-ash3/t1/551067_10203022916877614_1723932181_n.jp g" target="_blank">https://fbcdn-sphotos-h-a.akamaihd.net/hphotos-ak-ash3/t1/551067_10203022916877614_1723932181_n.jp g"/> [/img][/url]

EDIT: i dont know what a Halford "my first bike" looks like as i never buy bikes from Halfords...obviously you must do as you know what one looks like.....miaow back at ya!! 😛

I really don't understand this obsession with tall people trying to fit on a small / medium frame when manufacturers have spent tens of thousands of pounds (if not millions) designing a bike's geometry for a specific height.

Is it really 'personal preference' when all the bike hacks are using the word "chuckable" all the time, convincing you that you need a frame size equal to the BMX you rode as a kid??

I've moved onto a Ti post now.

Although the frame comes with a shim so as long as the seat post is inserted for the whole length of the shim it's ok bar the obvious extra leverage that more exposed post allows;

[URL= http://i239.photobucket.com/albums/ff167/LukeBurstow/DSC_0628_zpsd58793ed.jp g" target="_blank">http://i239.photobucket.com/albums/ff167/LukeBurstow/DSC_0628_zpsd58793ed.jp g"/> [/IMG][/URL]

Although mine isn't as extreme as some, my frame size was the one recommended by Paul at Cotic when I sent him my measurements and the geometry of the frame I was riding at the time.

That was a 16" but the 14.5" XS BFe was a closer match even though it needs a fair amount of post showing to get the saddle to pedalling height.

Perhaps it depends on how you ride. Most of the time my saddle is in the 'down' position (well, this is the important time). Bike feels great, and having picked up the frame for 200 quid I can afford to rethink if need be. I ride to slog up the climbs but enjoy the descents, fling the saddle out the way and see how far I can push it.

The frame's not going to crack, and yes, whoever it was above, the post is inserted 10mm beyond the REVERB min insert line, not some magical line on the frame! 😉

SO, if posts have these min insert lines on them, they must make them with setups like this in mind.

Ive not measured, but reckon my rail-clamp length is the same or slightly less than the clapm-BB centre line, which is alright!

Main thing is to make sure the post is below the min insert for the frame.

Proper Frankenbike...
[url= http://farm5.staticflickr.com/4023/4641090341_94c3987844_z.jp g" target="_blank">http://farm5.staticflickr.com/4023/4641090341_94c3987844_z.jp g"/> [/img][/url]
[url= http://www.flickr.com/photos/takisawa2/4641090341/ ]21032010287[/url] by [url= http://www.flickr.com/people/takisawa2/ ]pten2106[/url], on Flickr

The frame's not going to crack, and yes, whoever it was above, the post is inserted 10mm beyond the REVERB min insert line, not some magical line on the frame!

that would be me...

SO, if posts have these min insert lines on them, they must make them with setups like this in mind.

kinda, but no, I've had this discussion with many a customer in the workshop after cracked/broken frame.

The minimum insertion mark on a seatpost is governed by the design limitations of the seatpost and essentially means "if at least this much of the seapost is supported then it should not bend or snap based on the length of the post, the weight of a rider (with safety margin) and the expected loads we designed it for"

The minimum insertion depth for a frame can be, and often is, different, again based on the rider weight and expected loads, putting a longer post than expected (for given frame size) puts more leverage on the frame and may go beyond those design loads, especially if less post than expected is inserted.

Otherwise by your logic seapost manufacturers must have knowledge of every frame design and spec on the market in order to say what is safe, when really it only applies to the seatpost.

Often the two depths are broadly similar, but when dealing with frames with extended seat tubes or very long posts there is a concern and often the manual will say something like "insert Xmm below seat tube/tob tube junction, or Xmm below clamp etc. and this may be more than the minimum line on the seatpost.

General guide is 100mm of insertion past the end of the set tube will [b]probably[/b] be OK, but this is not a hard and fast rule. It really does look like you're pushing it based on your original pic, and I say that from workshop experience of seeing plenty of cracked and broken frames, and also bitter experience of cracking a couple myself.

I'm sure you'll be fine as generally the margins are quite generous and its a warranty arse-covering exercise especially on beefy frames like yours, but its definitely not something to be ignored.

I always buy frames that are too small for me as I like chuckable bikes you can throw around. Msot people who see me ride comment on how much "body english" I have i.e. moving the bike around, carving berms, popping off jumps and pumping through whoops. All of this is masked/made harder if you ride a bike that's the right size. I guess most people who do are probably "wheels on the ground" type riders, whereas I live for the descents. My only suggestion would be get yoursaelf on a skills course, it totally transformed my riding.