Custom Ti Frame Thoughts

Would appreciate a bit of feedback on a custom frame I’m considering getting fabricated, just to make sure I’m not trying to do something which is impossible 🙂

The bike is going to be my ultimate commuting machine, consisting of the following:
– Ti frame
– eccentric bottom bracket
– Di2 Afine
– belt drive
– dynamo hub lights
– 700cc 28mm tyres
– full mudguards
– hydraulic disc brakes
– drop bars

Getting all of those in one package isn’t exactly an off-the-shelf purchase, so I’m most likely having a frame custom made. I have already got hold of a cheap Charge Mixer frame which fulfills most of the frame requirements, but I’ll still have to cut the dropout to fit the belt. Considering having a ti frame made in China, and was contemplating exactly what I want.

Since fitting Di2 to my road and tri bikes, I love having everything internal, so I’d like to do the same for my wiring and hoses on my new frame. Adding an eccentric bottom bracket complicates things somewhat as you can’t really route anything through the BB shell, and as I’m going for Ti, it’s not as if there will be any big voids like you would have with a carbon frame. As such, I’m contemplating the viability of adding some tubular gussets around the BB shell to accommodate hoses and wiring. Quick solid model screenshots below:

There will be a Di2 battery in the seatpost, wiring going forwards to the cockpit for the shifter, and then back inside the chainstay to the Afine mech. Also running up the seatpost will be wiring for a rear light, and inside the down-tube and non-drive chainstay will be a hydraulic brake hose.

I appreciate that it’ll cost extra to have the gussets and access holes fitted, and it’ll be rather fiddly to get it all fitted, but hopefully it’ll be worth it for a nice clean look. Another consideration is potentially the distortion of the BB shell as the eccentric clamp is tightened.

Anyone see any issues with this? Any feedback appreciated.

Cheers, Rich

Aren’t most EBB’s an hourglass shape rather than a cylinder? Would the wires not get round it?

Edit: They already are quite minimalist.

[/url]
Singular Swift SS EBB[/url] by Singular Cycles[/url], on Flickr

Have you looked at http://www.milkbikes.com

Not ti, but they’d fulfil most of your other requirements.

I presume you’re getting someone like XCAD to make it? If you’re willing to pay I think they’ll do pretty much anything.

Having said that – I make my own steel frames and would probably want to kill you after trying to mitre those little stub tubes on multiple faces / compond angles 🙂 But then I guess they have to intersect everything – if they stood off from the bb shell then they would need tig welding around the full stub circumference (which would be equally impossible). It is the kind of joint that could be made in a variety of ways in steel where you just sweat silver solder around everything

http://www.spanner.org.uk/

Lots of info on people ordering ti frames direct..

Thanks for the feedback – TINAS, even if the EBB was hourglass shaped, how would you fit/remove the EBB after the cables were fitted, or how would you fit the cables after installing the EBB 😕

I think the extra gussets and access holes are required, but was concerned about stresses on these as the EBB clamp shell was closed. I suppose the method Singular uses of grub-screws to clamp the shell would eliminate this, and probably simpler too.

I have got a quote from XACD for the frame, but hadn’t thought about these features, which would most likely be a real PITA to do, but as it’s not me doing them, I don’t really need to worry 😀

Another question – am I better going for Ti or carbon forks? XACD can sell me some for ~$250, but if carbon ones will be better and not cost a huge amount more, then I’d choose them. The only problem I’m having is finding some decent looking ones with a post mount and bosses for mudguards and a light. Any suggestions?

Cheers, Rich

Thanks for the feedback – TINAS, even if the EBB was hourglass shaped, how would you fit/remove the EBB after the cables were fitted, or how would you fit the cables after installing the EBB

I was imagining sliding the bb half in, routing the cable, then sliding it in fully, not sure whether it would work though.

Can Ti have stuff brazed to it? Could you braze a bit of something like copper brake pipe arround the BB shell and make it a bit of a feature?

Couldn’t you run all the wires through the top tube? You’d need a hole in the seatpost extended seat stays?)or some other way of running the wire past that junction but easier than passing an EBB

Robin Mather builds in ti, I’m sure he could come up with a solution

A hole in the seatpost doesn’t appeal, especially as I’d need to remove it to charge my Di2 battery, so would need to either slot it all the way up to where the cables ran, have it super short, or remove cables every time I wanted to remove the post. Of course I could have a charging port for the battery somewhere, but my point still stands!

Ah, I’ve just understood what you mean by extended seat stays, as in they wrap around the seat tube….that might be a goer, certainly. I’ll have a think about that one.

Also, the brake caliper would be on the chainstay not the seatstay, so having a hydraulic hose coming via the BB would be the simplest route for that. Could look at having the caliper on the seatstay and brace it to the chainstay if I routed via the top tube.

That would get a hose to my rear brake, and a Di2 cable from cockpit to dropout, but be tricky for the battery and rear light…

Great input though, thanks!

Mark Lynskey always suggested that extra bits on Ti frames usually cause more harm than good, as extra heat going into joints isn’t a good thing.

In that seat tube area where there’s lots of torsional and loading going on, along with clamping forces and the cyclic compressive stresses of pedalling on the chainstays, I would predict cracks forming on the driveside of the seat tube at 3 o clock, then wrapping backwards round the seat tube.

To add those gussets just to hide cables is in mechanical sense, complete madness.

I’m sure it could look lovely.

The mitring will be a complete nightmare.

I don’t know if anyone would actually take it on.

I’d armour the cable with something fun, or pink pipecleaners.

Ray’s Rohloff tourer

Steel, but ticks the other boxes I think…….

Talk to Enigma. Never met an unhappy owner. Smug ones, but not unhappy.

Brant, thanks for the input, someone who perhaps knows wha they’re talking about 😆

Assuming I don’t want wires on the outside of my frame, what about large breather holes for the hose and the cables to duck in and out through that area, instead of being boxed in – any thoughts on that?

A hydraulic hose on proper guides on the outside of the frame isn’t the end of the world, but Di2 cables and wiring for lights is something I really want to avoid.

English does make some beautiful bikes, but I’m not planning to pay quite that sort of money, or wait several months either. I think the budget would rule our Enigma too!

I’m starting to sound very fussy I’m sure, but I’ve never been a fan of the big clunky Rohloff shifter, hence the Di2, and the Shimano hydraulic road levers are only Di2 compatible.

I still need to find a carbon fork which will take discs, guards and have a mount on the front for a light, without resorting to mounting one on the side of a rack as the English does. Actually, Spot seem to do a fork which fits the bill 🙂

Cheers, Rich

wait for wireless shifting?

Sliding dropouts would make the BB area much easier 🙂

And you do know you don’t need to remove your battery to charge it don’t you?

I’ve seen some very neat ones done with tubes through the DT and CS, with just a bit of cable or hose running over the BB shell – once the cranks are on it’s pretty unnoticeable.

Brant, sliding dropouts would be easier, I appreciate that, but I’d prefer the messy bit to be out of sight, and the dropouts to be nice and simple, hence the EBB.

Ben, I think that’s the way forward, certainly much simpler than trying to keep it all internal. Couple of models below – purple is electric wiring, black is hydraulic hose.


2 questions:

1) any thoughts on the positioning of the access holes – should these be moved further away from the BB?
2) which is generally deemed better in terms of EBB clamps, the first or second option? The third is what I have on my Tinbred at the moment with internally expanding wedges, but I don’t think those will be easy to adjust with external bearing cups.

Cheers, Rich

Hole positioning looks reasonable – for neatness you might want to have two holes on the underside of the DT.

I’m not a fan of the grub screw type of EBB fitting – the grub screws can create a burr on the EBB which makes adjustment harder, and threaded holes in titanium can be a problem sometimes.

I’ve not had a problem with expanding EBB and external cup BBs.

Hole positioning looks reasonable – for neatness you might want to have two holes on the underside of the DT.

I disagree, but you are an actual frame builder.
Holes on underside of CS just feel like being in the wrong place.
And holes in DT and ST there… hmm… Longevity isn’t going to be helped.

As TINAS says, the hourglass shape of set-screw/clamp up EBB’s mean that getting the wires through would be OK internally I’d have thought.

Don’t forget..once the ‘EBB’ bit is in the frame, the BB fits INTO that.

I.e – once fitted and cables routed, you wouldn’t really need to remove the ‘rotating part’ of the EBB. The standard BB simply fits into that bit.

ergo, it would be a fit once job, then you can switch teh standard BB as you like, without needing to alter cables.

DrP

All those holes facing downwards under the BB would worry me. Heres a pic of extended seatstays with an internally routed rear brake.

JRD seatstays

I disagree, but you are an actual frame builder.
Holes on underside of CS just feel like being in the wrong place.

Though I work mostly in steel, and I’d do those with internal pipes – which I presume you wouldn’t have with titanium. Internal pipes don’t weaken the tube.

I’ve definitely seen much neater layouts where the cables go over the shell, it’s a straighter line that way. Or another way would be to use sliding dropouts, with an oversized DT that extends below the BB shell – that way could have the cables exit under the shell in a straight line. Again, would look very cool in steel, not sure how it’d work in Ti.

Thanks for all the feedback again.

My experience with the EBB on my Tinbred is that the adjustment screw is very close to the BB shell (it’s running an old-school ISIS BB) so I was wondering whether external cups would get in the way of adjustment. Maybe I need to have a closer look at the mechanism, the only minor issue being that the bike is in Sheffield and I’m in India 🙂

Although there would be clearance for cables to pass through the central section of an hourglass type EBB, if the cables protruded into the shell space when fitted, you wouldn’t be able to insert the BB after the cables, even if there was space when it was in. Also, I doubt whether the void which the shape gives would allow access to the CS, so some of the cables would have to go outside the shell.

While the extended seat stays look like a very neat solution, it doesn’t quite work for me as my caliper will be on the CS, and it doesn’t solve the problem of getting cables out from the ST.

At the end of the day it’ll be a relatively cheap Chinese frame, and hopefully with some little strengthening rings around cable holes there shouldn’t be too many cracks propagating from them, but if they do appear, it won’t be the end of the world.

Cheers, Rich

ctk plus 1.
You could run the power cable from the seatpost battery down and through the ebb up to the ht, then route brake and shift cables from ht along tt and down ss; your own take on GT triple triangle like an old Xiang.
Are you planning to run cables for lights too? The little ‘Plug’ device or similar mounted in place of hs top cap could be worth including also.

Just to illustrate my point about expanding EBBs, the original expanding mechanism on my Tibred was this:

and I changed it to one of these to save some weight:
Neither of these have any space for cable routing, hence my thoughts for the external cables.

Will give more thought to ctk’s idea, how I could get a brake hose to the CS from the SS without looking really ugly and contrived. Alternatively I mount the caliper on the SS and brace it down to the CS.

Ah, I’ve just realised that as I have a break in my SS to fit the belt, that somewhat rules out cables in there….

Bike will have a dynamo, one of the cables I’m planning is power to a seat-post mounted rear lights. Milk Bikes actually have a nice post with integrated LEDs.

Cheers, Rich

I think that with sufficient internal chamfering, I can route the ST-DT cables internally through a port in the EBB shell, thus:

A slight improvement from the original mess 🙂

Thanks for all the imput guys, much appreciated.

Cheers, Rich

That’s still going to be a total PITA to route, best find a child with small fingers 😉

Another factor – with unguided internal cables you’re going to get some rattling.

Ben – the word you’re looking for is challenge 😀

I have internal cabling on my road and tri frames without guides and I haven’t noticed any rattling, but I agree the hydraulic hose might be noisier. If I have an access hole into the DT from inside the HT then perhaps I can stick some foam in to dampen things down. Of course this would inevitably get stuck and be a major ball-ache in the future when I needed to run cables in future 😆

Cheers, Rich

What about using a Niner BioCentric EBB? Can be fitted with cables in place, looks like there is loads of room round it for them…

The Biocentric looks like a nice elegant solution, will definitely investigate one of those.

Cheers, Rich

I know you will all be keen for an update 🙂

Ordered my frame from Titan Products who have been very happy to comply with all of my bizarre requests. As the Di2 Alfine has a rather narrow chain line, which is made even narrower when you add the belt drive. When you want clearance for decent sized tyres and guards it necessitated a scalloped drive-side chainstay for clearance up front.

The Biocentric is a very elegant EBB solution, but it changes a 68mm shell to a 73mm after fitting. This is a bit of a no-go with the chainline issue, however with some subtle machining on the internals of the EBB, and a 63mm shell, I’ll be back to 68mm.

I’m hoping that the purple wire shown there will be able to be routed inside the shell, but in case I can’t manage it, I’ve made sure there is a cable orifice on the chainstay to accommodate it.

I ordered forks, bars and post a couple of weeks ago which are now sat in customs in Mumbai and I’ve just ordered all of the rest of the components from Germany. I got the rims a little while ago along with another set of wheels for my tri bike, so hopefully the whole thing isn’t too far away 🙂

Dynamo hub up-front to power a Supernova E3 Triple and a Tailight 2 which I’ll mount inside my post similar to this:

Build pics to follow soon!

Cheers, Rich

Dynamo hub up-front to power a

what no on-the-fly Di2 charging? 🙂

and £? ❓

Di2 charging might be something I’ll look into – certainly no reason why it shouldn’t be possible, however I don’t want to fry too many batteries in the attempts 🙂

I’ve ordered a pukka seatpost-mounting Shimano battery for my TT bike, so I’ll cannibalize the old battery from that bike to shove inside this bike.

Cost breakdown:

Frame (Chinese titanium) £580
Forks/post/bars/rims (Chinese carbon) £378
Hubs/Cranks/Di2 bits (Alfine) £441
Belt drive kit (Gates) £263
Brakes/Shifters (R785) £420
Lights (Supernova) £165
Misc (spokes/headset/tyres/EBB etc) £188

Grand total roughly £2435 plus a few bits I already have spare (saddle, pedals, tubes) Certainly not the cheapest commuting machine ever, but hopefully it’ll be nice to ride, virtually maintenance-free and pretty versatile.

I can also offset about £150 from selling my Langster which it will replace 🙂

Cheers, Rich

You might save on the belt system going to http://www.bikeparts.com/
Depending on delivery charge and import duty.

I had originally looked at the bikeparts website, but they don’t stock any of the Di2 components. Unfortunately the Alfine Di2 has a different belt-line to normal Alfine to clear the motorised shifter unit, so the parts aren’t cross-compatible. This leaves me ordering from Europe at a higher cost.

Cheers, Rich

Interested to see pics when you get it.

BTW how far is your commute?

Titan Products quoted 35 days to manufacture, then it’ll be a few days to get to India, then probably several weeks to get it released from customs, so I’m expecting I’ll get my grubby mitts on it mid-September ish.

Won’t be built up until I return to the UK, which I hope will be in October, but all of the components have arrived from Germany so it’ll be built up pronto after I arrive back in civilisation!

Commute is only 14 miles direct, but I can extend it to include some loops around Box Hill etc when I want some more distance. Clearly it’s not exactly necessary for a half-hour commute, but I’m reckoning that this bike will be useful for a bit more than just to and from work 🙂

Cheers, Rich

14 miles in half an hour is good going on the commute. I’m guessing you don’t have many traffic lights round your way?

I think there’s some rounding in there!

Bike looks really interesting – be good to see the finished article.

Ah, my mistake; I was mixing kilometres and miles, using my general 30kph as a typical average with occasional lights, so yes, it’ll be more like 40 minutes. Not tooooo many lights in my journey, but to be fair I haven’t really ridden it yet as we’ve just bought a flat so haven’t moved in yet.

It’ll be ~90 minutes to run which I’m planning to do fairly regularly too.

I’ll be picking up my Alfine hubs from home this weekend, and I have the rims in India, so building some wheels will keep me busy for a few hours in anticipation of the rest of the build.

Cheers, Rich