hello

Hope you can help. I am trying to find out the seat post size of a 1981 Bianchi Rekord 748. Does anyone know?

Thanks
K

Hi Katy, welcome to the forum. can you tell us a bit more about the bike? do you know what tubing it is made of? is the bike in the US or some other country? Pics?

check your local shop. lots of shops here have a set of guages, something like a Jeweler uses to check the size of a ring. if a shop near you has a set or a good pair of callipers it will be a snap to figure it out.

I bought it online. I've been given the wrong seat post so I am trying to find out the size online (lazy...) .

Tubing is Columbus Zeta.

I'll take it to my bike store for a proper measurement. Be right back

Took it the bike store and got a seat tube diameter of 26.4-8mm

Also does anyone know where I can get hold of a seat clamp bolt? I bought one but its not a perfect fit..(the original one snapped...)

I'm in the UK. So need to source one online or just tell me what I should be looking for size wise?

Uhh... Take it to a different shop. Seat posts come in increments of .2mm for a reason. If you try using the wrong size post you will have problems. Go someplace that will test fit posts and then you can know for sure which one fits.

As far as the clamp, oftentimes a plain nut and bolt will do just fine. If you really want the correct clamp I'd say your best bet is probably ebay.

Yeah I wasn't too comfortable with the range that I was given. I think I took it to the wrong bike store, should of tried somewhere that doesn't just deal with certain bike brands. I don't think his digital calliper was the most accurate tool for the job - I was really hoping they'd have one of those seat post measuring rods...

The current seat post that I have on it measured 26.4 and very almost fits..
I think I'll be trying a 26.6mm seat in the next few days..

So stressful..I really want to ride this bike! (without the seat swivelling

I'll let you know how it goes...

Thanks for the help..

sorry to hear your having trouble. you actually should be able to get a post right there at the shop.

the store that I went to only? stocked alloy posts etc which the person advised against doing against my steel tubing. I'll be receiving a 26.6mm next week so fingers crossed that that will be fitting!

Wow don't go back to that place, ever. That's major strike 2. Aluminum posts are perfectly fine in a steel frame. In fact, I don't think I've ever even seen a decent quality steel post.

Just an update (for future reference..or whatever):

Seat post 26.6 fits. It's quite tight (doesn't just slip in) however I think this might be something to do with the seat tube. I noticed today that there is a small bump behind where the seat clamp is... So I think thats one reason why the seat post is tight. So fairly certain that 26.6 is the size...

I'm kinda shocked by how fast this bike is (having come from a hybrid type bike). The 20mm tires are scary...Hope to change to something wider in the future (but thats for another thread

Katy,

That's a nice bike, I like the rekord.
Agree that you should stay away from that shop, they know not what they speak of.
There are plenty of shops in the UK that know about vintage bikes, I'd suggest
finding one of those.
you'll get used to the 20cm tires, but you can always put on a 23 or 25cm tire.

Marty

edit: I'm moving this into regular C&V forum it's not an appraisal request!

I owned one of these a few years ago and the post was either 26.8 or 27.2, it definitely was not 26.6. I'm thinking 26.8. The seat-tube is probably bunged up, or the ears have been squeezed if a 26.6 is tight now.

A proper bike shop can fix this for you.

hmmm

The original seat post I was given was 26.8 and it slid in quite comfortably but no matter how much I tightened the clamp, it would still move...

Ahh I don't know..It's fitting now, even if a little tight, but I think if I wanted to take it out (in the future), I would not need to resort to drastic measures (I hope!)

I am not certain but I think Record bikes came in several models like your 748, also just because a 26.8 post fit in a US market bike that does not gaurentee a UK bike will be 26.8

I am with Lotek 20mm tires do take a bit of getting used to but I perfer a 23 or 25. for me the difference is speed is not noticable (if there is one) but the ride comnfort improves esp with the x25s.

13 post and no pics?

Glad to hear you are finally riding and enjoying your Bianchi

I may put some photos up on my flickr in the future, don't feel it's ready for a photo shoot yet (need to get my SLR repaired).

Just replaced the previous owners saddle with a Brooks, it's the first time I've used one - quite surprised by how comfortable it is as I was sceptical of the hype..

Also need to decide on bar tape and whether I want to change the brake levers (finding the current ones quite hard to reach from the brake hood position with my small-ish hands)...decisions decisions.

Yeah definitely wider tires in the future - too much wind and rain around this area.Don't feel too confident with 20mm.

Often times the cavities on a vintage bicycle frame set could use some attention, particularly the seat post cavity which is subjected to all kinds of maintenance issues, some of which are at the hands of someone who knows little about what they are doing. With that in mind, I wrote an article on Fame Cavity Preparation which might help the OP understand some of the things that impact getting the post to fit and stay where it should be.


Hope this is a help.

I have a 1980 Bianchi Rekord 748 with the original seatpost. It is 26.6mm.

Just remember to grease an aluminum post when installing it in a steel frame. ALWAYS.

(Just adding this caveat for the lurkers seeking and gaining expertise).

-Kurt

(...apologies the very late reply...only just notified of the updates in my inbox)

Yeah you're right. Got the 26.8 replaced with a 26.6 and although it is slightly tight...it fits much more snug than the 26.8.

I have a bike which I *think* is also A Bianchi Rekord 748 (i tried to post an image but this board only allows images after a threshold of 10 posts.....)
I have the original seat post but it has no markings so I do not have a reliable measurement for the seat post width.
I ordered a 26.8mm diameter seat post but on testing it I can confirm that is too wide.
I also tested a 26.4mm diameter post which seemed to fit easily.
I have ordered a 26.6mm and I hope that hits the sweet spot.

I can't recall seeing a 748 with chrome fork ends. Typically they were fully painted. Perhaps we should start with the serial number, which would tell us the year, and work from there. Based on the frame features, it would appear to be early 1980s. If so, the serial number should be in two parts, one on each side of the seat lug.

After some annoying and costly mis-orders I can now confirm that a 26.4 is the correct seat post for this bike (i needed a 350mm one for height - much longer than the original). I got an 'Accent' seat post - i seems reasonable quality and the logo is the least offensive I have seen (i prefer no logo)

For the 'rekord' the serial on the head tube is 8N31121. Only number I can find!




Head tube serial number

Great site - so frustrating that I cannot post images or links to provide better info

But try Googling an image search for 'Steel Vintage Bikes - Bianchi Rekord 748 Late 1970s Vintage Road Bike' for a very similar looking silver bike

Another pic assist: