Is shortening a stem worse than lengthening it?

bigflangesmallsprocket

beat me to it manc! What spacers did you use in the end? if you used em all, you can make it look a lot neater once you've dialled in the height by getting just a single long spacer off Ebay.

diamonddog

The tapered top cap is part of the headset so 40mm above that is the max for spacers below the stem, that is how mine came from new but I have since lowered it. I have seen other views stating 50mm max but TBH I think 40mm is ample.

Manc33

bigflangesmallsprocket wrote:

Would that tapered top-cap also count as a spacer? Really, you do need to keep max allowed height at first, just for safeties sake. If you cut it low, find you can't reach and have to flip the stem to make it fit....you'll be sorrrrryyyyyyyy

Yes the top cap thing (came with the headset, made of carbon) is 15mm tall.

Its setup like this from top to bottom:

--- Bolt and top cap ---
- Spacer, 5mm
- Stem, 40mm
- Spacer, 5mm
- Spacer, 5mm
- Spacer, 5mm
- Spacer, 5mm
- FSA carbon spacer, 15mm
--- Concealed bearing inside head tube ---

So I have 35mm under the stem and 5mm on top.

bigflangesmallsprocket wrote:

No, Specialized are not saying the cap takes the strain. It's simple but clever, the top-cap allows micro adjustment of the headset...you just tighten it up enough to give correct play for the headset bearings, so the fork doesn't waggle from being loose, or the bearings grind from being too tight. It's the stem clamp that takes the strain.

No I mean when you tighten the stem bolts, the Deda bung is inside the top of the steerer taking (I can only guess) some of the strain, so you're not tightening a stem onto a hollow tube, the bung covers the 5mm spacer plus the 40mm stem - just about.

diamonddog

So you have 20mm of spacers under the stem which is half the recommended max.

Manc33

diamonddog wrote:

You have 20mm of spacers under the stem so half the recommended max.

20mm of spacers and also the 15mm spacer as well.

I just did a test, dropped the 3" tube from about 8 feet onto concrete, nothing, it just bounced. Stood on it and rolled it under my foot, nothing, still round. I tightened that clamp/spacer onto the very end of the tube, folks I didn't have to really go that overboard tightening to make it crack! This is the spare tubing I am talking about not the steerer.

Wonder what the bear minimum Nm is to keep the stem from slipping.

diamonddog

I know what you are saying but you could have had another 20mm of spacers, the bearing cover is always there so is not part of the equation, but if you are happy with it then that's what counts.

bigflangesmallsprocket

I have to admit, I'd have thought that the headset cap, being as tall as it is, effectively a spacer, lots of headsets have very short height headset tops. The deed, tis done (if that's not a quote, it should be )

bigflangesmallsprocket

I think I see what you're saying manc, that the bung expands and acts to reinforce the carbon steerer, adding a bit of strength. Not having used one, I'll take your word for it

Manc33

Bottom bracket is in, went in smooth.

Those bizarre down tube adjusters are screwed right in and backed off a turn, assuming you undo to tighten the cable like with other cable adjusters?

Brake calipers now...

Manc33

I wonder what the torque should be (on a carbon frame) on brake calipers. I know when I took those calipers off they were on pretty loose, but that could have been my wiggling.

People talk about the front mech band mount and the stem bolts, but what about brake caliper bolts?

Seems like an area that takes more stress than a steerer tube does.

bigflangesmallsprocket

Are you using a torque wrench? If you are, then a bit of googling should tell you what settings you need. Otherwise, just tight is tight enough, to be on the safe side, till you get more info.

As far as specific info on carbon frames goes, me giving advice would be like the blind leading the blind 8) ...wheres me stick..

By the way, have you had a look at the view numbers for your thread. You've got a few folks following your build on the quiet :P

rolf_f

Even if you have a torque wrench, you probably don't have a bit for it that will go far enough in to reach the nut. Besides, the brake bolts into a solid chunk of thick carbon. If you can crush that by over-torqueing it then probably you go green when you get cross.

Manc33

Not looked at the threads viewing figures / ratings, no. :P

People have snapped stuff torquing it using a torque wrench anyway. :roll: I know most people probably tighten to what it says on stuff when that is the max.

There'd be more pics up, but the camera battery is taking a while.

Up to now its got the fork properly on, stem, bottom bracket in, both brake calipers on and the back wheel is on just to see how the brake pads line up and if putting weight on it flexes it... that back fork clearance is close, but I couldn't get it to go tighter putting weight on it. I keep forgetting carbon is so stiff... and yet soaks up bumps.

You know what was scary, sanding the steerer tube, not because of fraying threads (if there were any I didn't see any) but it is how it just turns into black dust when sanded. :shock:

Its like its made out of charcoal lol. Just an extremely strong charcoal.

Ever seen this video?

https://www.youtube.com/watch?v=FKrZxXQ2ac8

Manc33

There's one thing I had to get done at a bike shop on this, that non-split ring on the fork crown. The thing the bottom headset bearing rests on. If I had a 36mm metal tube that was a few feet long I would have tried it myself. :oops:

I have pretty much built the entire bike tonight including getting the seat at the right height.

The reach is just about perfect (not just saying that because I just bought it honest) with the 90mm stem on off my MTB. The Triban 3 originally came with a 110mm but I put the 90mm on straight off and it seems comfortable. I am not reaching like I was on the Triban 3 and I am certainly not squashed up on it.

The only things missing now are the front mech and its mount, rear mech, chain, the 4 cables.

This looks all bent but it isn't. :P Stupid camera lens. :roll:





I can tell its ruddy light already, although there's a good 700g+ to add yet.

How many miles will I be riding it before I have to put that 91g carbon saddle on and get some GP4000S tyres?

lol @ that triple "30-39-50" nope... its 28-39-50. Shhhh don't tell anyone.

Manc33

Above: First blade used to cut steerer. Had to use another then another after this one. Who said carbon is soft?

Below: Brand new hacksaw blade.

The one used on the steerer has practically no teeth left on it. :shock: Might as well have been using an E string guitar wire to cut it. I mean string. :x



If you used one blade you'd be there for hours. A new blade cuts it pretty fast but the blades go bad about a third of the way into the tube.

k-dog

Next week are you going to paint your radiators?

Manc33

k-dog wrote:

Next week are you going to paint your radiators?

The radiator with a bike in front of it? :P

It is in the process of being done, the wall is pink around it because its only just been replastered.

I told you, that radiator is like that from 25 years / three generations of people putting their bikes next to it, 75% of which were flat bar bikes where the end stops were long gone. Every single bike I had as a kid ended up with the bar ends either battered into the bars or fallen off before they had the chance to. My bar ends were normally plugged with mud.

I wonder, if I post that pic on a radiator forum, will some guy will ask me when I'm putting a chain and cables on my bike?

Kinda glad its raining out lol. I've got no bike to ride. Bucket it down now and get it over with.

Saw a lot of people out on bikes today. Saw one guy walking around the streets in shorts! :shock: These are the people I want in the army. He can go out in shorts in winter, get on the front lines.

bigflangesmallsprocket

Looking good mr manc

You did the right thing using the shorter stem to start with, you don't want to risk your back by forcing your position.

That saddle doesn't look like a B17, that looks like a Colt to me, though it's still a Brooks. A nice looking saddle. A relatively new model in the 80's I think (recently brought back into production) fashioned to look a bit like the Rolls and Turbo saddles of the period; nice find.

You've probably noticed those Brooks saddles sit a bit forward compared to modern saddles. If you can't get it comfy then a set-back seat-post (seat-post with the clamp for the rails set further back) will cure it. Otherwise you might find yourself sitting your bum-bones on the metal part of the saddle on the rear..I've done that, it's not recommended.

Manc33

bigflangesmallsprocket wrote:

That saddle doesn't look like a B17, that looks like a Colt to me, though it's still a Brooks. A nice looking saddle. A relatively new model in the 80's I think (recently brought back into production) fashioned to look a bit like the Rolls and Turbo saddles of the period; nice find.

It is a Colt. Thin for a Brooks, but still fat. My father bought it around 1991, used it for a few years on a touring bike, then stopped cycling and it stayed in a loft from 1993 to 2012. It was bone dry after 19 summers in a hot loft. I revived it with olive oil and its back to new. I can't justify taking it off even at 570g. Too comfy, can't even feel it. If it were possible to ride 500 miles in one go I wouldn't feel it.

bigflangesmallsprocket wrote:

You've probably noticed those Brooks saddles sit a bit forward compared to modern saddles. If you can't get it comfy then a set-back seat-post (seat-post with the clamp for the rails set further back) will cure it. Otherwise you might find yourself sitting your bum-bones on the metal part of the saddle on the rear..I've done that, it's not recommended.

Didn't even look where I was putting it on the rails but it is more at the back. When I sat on it before I tried every position and it wasn't like I was reaching as much to get on the hoods as I was on the Triban 3. This Stelvio is 9cm smaller than the Triban 3 was though lol. I like how its only 1200g. 1194g on my scales and 356g for the fork, after cutting. That brings the frame and fork to exactly 1550g. The Triban frame weighed 1911g (the guy quoting 1995g on triban3owners for a 57cm had the headset still in ) and I didn't weigh the fork - around 580g I think, making the Triban frameset just shy of 2500g. So I spent £350 and shaved nearly a kilo off my bike.

Can't think of any other way I could have done it after already getting a lighter wheelset.

I wrote the reach down somewhere, I will compare and see if I am talking out of my a***. The reach feels shorter but if its the same then its "buyers fallacy". :oops:

diamonddog

Build is looking good Manc33.

Manc33

Cheers diamonddog. It feels way better than the Triban did for the reach just sat on it. Its easier to get on and off with the lower top tube as well. Particularly useful when you have no brakes or chain on it and are trying to get on and off.

Band clamp doesn't seem to be arriving today.

Not surprised in this weather.

There's really nothing else to put on the bike.

All I have now out of my bag of bike bits is the lights, battery packs for the lights, bike computer, bottle cages and bolts, rear mech (gonna clean soon and put on) the front mech because I haven't got the carbon mount yet, chain and cables.

Its amazed me how quick it got built if I took all the faffing out and the fact that I didn;t know what I was doing with some of it. Someone knowing what they are doing could build an entire bike in under 30 minutes I am sure. I wonder what the world record is.

Bike can't be completed today without that FD band mount but it would have been.

Do you really think I would go out in this weather on it anyway. :oops: Maybe after a few weeks of riding it but not straight off. I have a nice new chain for it (the original Triban 3 chain I can't even remember why I took off).

What was it for the chain "big to big plus 2 links" ignoring the rear mech? I will just count the links in the old chain.

Don't chains come as 114 links as standard? How come they are so long? Mine with a 50F and 32R only has 106 links I am sure. Not sure what most road bike chains would be on a 39/50 and 12-25T setup, about 102/103 links? What purpose would there be for 114 links? A tandem?

Manc33

Why is the B tension screw 80% hanging off the edge of the rear mech hanger?



I have to have that screwed all the way in to cope with a 32T MTB cassette.

The angle of the hanger (where that notch is) is not the same as on the Triban 3.

Manc33

What does it mean?

I lined up the frames so the chainstays were both parallel.



The notch on the Stelvio hanger is a lot further up/back than the Triban 3.

This could be the downfall of the whole build. :shock:

I can't ride on a road cassette, having low gears is more important than having a new frame.

Wait, both these hangars are removeable... but have nothing like the same screw holes. :x

If I back off the b-tension screw about 4 threads, it is half hanging off, but then the drivetrain might "rumble" in the lowest gear. Did on the Triban. Can't tell anything until its all setup.

Might screw on the 2300 road rear mech I still have just to see what the deal is with the B tension screw.

EDIT: Tried that 2300 rear mech and its not as bad but the b-tension screw still overlaps the notch on the hanger.

Ben6899

The size of cassette you can fit is limited by the rear mech type and the chain length; not the frame.

I can't quite see what you're getting at, but I don't think we're seeing the 'downfall of the build'. Chin up... someone more technically astute will be along in a moment I am sure!

Manc33

The b-tension screw is half overlapping that notch though, it shouldn't be like that regardless of anything else.

I know the mech can only take up to 34T (2 more teeth than I use) so it won't be possible to back the b-tension off so much it still copes with a 32T.

Got the carbon band mount now though. Heard a few little crackles when I tightened it (slightly). :roll:

I wonder how much weight 3Nm is on the end of a 70mm allen key. :oops:

If its that loose how does it hold the front mech securely? Seems like theres no margin for error here. Like 2.5Nm would be the least to hold it there and over 3Nm will break the band mount.

I know I should have a torque wrench but it would have to be a cheap one and none work as far as I know. Ones that would work like Park Tool cost nearly £100. For something I am going to do once a year or whatever.

rolf_f

Manc33 wrote:

I know I should have a torque wrench but it would have to be a cheap one and none work as far as I know. Ones that would work like Park Tool cost nearly £100. For something I am going to do once a year or whatever.

http://www.ribblecycles.co.uk/sp/road-track-bike/tools-bbb-torquefix-tool/bbbatool250000000000

This is fine at less than half the price. Park stuff is very variable so don't assume that because it's Park, it's good. Some is, some is crap.

Manc33

Front mech cable (the straight bit between where it comes out of the frame and it connected to the swingarm) interferes with a riveted bolt on the front mech itself. After so many changes to the granny ring it would eat into the cable eventually and with the cable coming out of the frame at that angle it would probably eat into the frame too.

Maybe its because the front mech is a R443 which is apparently meant for flat bar shifters.

I don't have a braze-on triple road front mech and would have to buy one if this won't work.

Looking at my Sora front mech it has nothing like the same setup on it as the R443 where it might rub the cable. It never would rub the cable on the Sora because there's nothing there to interfere.

Maybe I can get it to shift to the granny ring and have the cable on the very limit of touching the front mech, not got to that part yet, need to clean my chain first. Why I didn't buy a new chain I have no idea. :oops: Can't use the (nearly new) KMC off the original Triban 3 because it has 106 links and I need 110. Well the KMC has a powerlink so it has 105 links not 106.

Unless I can mix and match SRAM and KMC chain links.

bigflangesmallsprocket

hi manc, see you're forging ahead!

Just a few thoughts. I'm not sure that winding the screw back just a little will do any harm, but you'll get a better idea of how it actually behaves once the chain is on, until then there's no need for any panic! Anyway, from the comparison pic you posted, the Stelvio mech does seem to be sitting back further than the Triban; if that's the case, then bringing the mech forward slightly will merely bring it back to the same equivalent position it was on the Triban.

Front mech. Have you actually fitted the mech and set it up, to see if it still rubs when the mech is lined up over the chainrings? Once it's all lined up it might have enough clearance, and from your post I'm guessing that you haven't?

If you've had a fair bit of mileage out of your chain (which I'd guess you have from what you've said of the condition of the bearings), best to change it. The chain, or rather the little pivots/bushes wear quickly and stretch the chain out, which then makes your sprocket and chainset teeth wear out quicker. Changing your chain regularly makes the rest of your set-up last a lot longer.

Manc33

Up to now got both brake cables in and all setup. Calipers are tight, cable is in tight, pads are setup and tight.

Its getting very close now to being 100% done.

Still got the front and rear mech cables to put in and put the chain on, then see if I am going to have to use this as a double chainring or not.

Its not the frame anyway, its that silly R443 front mech. I can see the Sora front mech is nothing like that and the cable coming out of the Sora can't rub anywhere on itself like it can on the R443.

I am not sure if theres a "Tiagra R443" and then a mech simply called "R443" thats nothing to do with Tiagra? Tiagra is all road components.

I have a Sora with a metal band I don't want to risk and a braze-on of the R443.

What I might need is a front mech/road/triple. Thing is triples are seen as a laugh and you'd never get a new Ultegra or DA "triple" thats also 8 speed, maybe in 1988.

So if I have to get one I will just have to settle for some crappy cheap one thats 8 speed and a triple. Honestly, specifying 8/9/10 speed on a front mech is just going too far. :roll:

Once its all setup I will do pics.

If you want a close up of a certain part of it let me know what to do a close up of.

bigflangesmallsprocket

Right, I've just had a google! I may have some answers, but need more info. As per usual, looking on forums I found different opinions for the same questions..typical..

Would I be right in recalling that your triple chainset is actually an mtb one?

Is your triple chainset a Shimano brand?

Did you have the triple chainset on the Triban?

When you bought a new bottom-bracket, did you get the same width spindle as previous?

Shimano square taper (and possibly road-chainsets) mtb chainsets seem generally to require a longer bottom bracket than a double, so this may be an issue. Do you have a spare wider bottom bracket hanging around?

The R443 front mech is flat-bar specific, meaning that the flat-bar shifters may move the front mech a different amount to say, a drop bar shifter on Shimano. Also, on some Shimano sti shifters, there seems to specific shifters for double and triple, whether this applies to yours, I don't know.

I have a fairly narrow bottom bracket on my mtb groupset Carrera Subway, but then again, I did stick a non-Shimano chainset on to get a specific fit.

The answer may be that If you have a Shimano flat bar front mech, and a Shimano mtb chainset, then you may just need a wider bottom bracket. Whether the front mech lines up into all three rings using the sti shifter is another matter!
EDIT: meaning that fitting a longer bottom bracket will move your inner chainrings out, and therefor alter the extreme inside position of the front mech, possibly allowing the cable to not rub on the mech.

DOUBLE EDIT! If you had the triple chainset fitted on the Triban, were you able to use it with the sti-shifters previously, and across all three chainrings?