Author Topic: Pact Ti fix  (Read 7855 times)

Chris N

Pact Ti fix
« on: 13 May, 2016, 11:08:45 am »
Just placed an order for my first custom frame, designed by Brant at Pact Bikes. Geometry was based loosely around the Planet X Kaffenback 2 which he also designed - I used to own one and liked the way it rode. Frame is being made by Waltly Titanium in China.

Other bits of the spec:
Long 44mm HT (no spacers under stem, tapered steerer)
Same reach and stack as my Synapse
CX fork (400mm A-C, 45 mm offset)
Long-ish chainstays
Short seat tube, long post
Clearance for 32mm tyres + guards
Single chainring at 53mm chainline
Disc brakes with adjustable dropouts
High BB
Rack mounts, 3x bottle mounts, external cable routing

Frame drawing:


I added routing for a rear derailleur just in case I want to run it as 1x at some point in the future.

Have got the following parts already:
Wheels - Surly ultra new fixed/disc rear, Shimano XT dynohub front, Stans Alpha 340 rims
Panaracer 32mm Gravel Kings
B+M Luxos U light
Thomson post and Cambium saddle
Truvativ stem
FSA Vero bars, SRAM S500 levers
17T cog
Mechanical disc brakes from the Synapse (Bengal MB700T) + 160mm rotors
SPD-M540 pedals

Frame should be here by the end of next month and I still need to get:
Kinesis Tripster fork - only full carbon tapered fork I could find with QR dropouts, mudguard mounts and a through hole in the crown for a dynamo light bracket
Cane Creek ZS44/28.6 EC44/40 headset
Mudguards
Cranks, BB - have got a pair of old Shimano 600 road cranks on the way, will probably have to use a 125mm BB to get the chainline I need.
43T or 44T chainring
Seat clamp
Chain, cables, etc
Might upgrade the brakes to TRP Hylex - have got BB7s on another bike and they're OK, but fancy trying the hydraulics.

vorsprung

  • Opposites Attract
    • Audaxing
Re: Pact Ti fix
« Reply #1 on: 13 May, 2016, 02:32:37 pm »
Side entry bottle cages so you can have a frame bag?

On my new bike I am going to have a IQ-X 100 lumen light instead of a Luxos-U.  Not sure if I am going to get an external charger like a zzing or just not bother.
The IQ-X looks more weather proof to me than the Luxos-U

Chris N

Re: Pact Ti fix
« Reply #2 on: 13 May, 2016, 03:19:28 pm »
Yep, though most of the time I'll have a frame pump under the TT.

I've already got the Luxos U, been using it for a couple of years. Otherwise I'd fit an IQ-X or maybe Edelux II - though I have a feeling that the Luxos remote switch won't last much longer anyway.

rogerzilla

  • When n+1 gets out of hand
Re: Pact Ti fix
« Reply #3 on: 14 May, 2016, 10:16:33 am »
Is the riding position fairly far back, with a short stem?  Having ridden and owned several fixies, a bike that won't easily lift its rear wheel is a good thing to have on fixed.
Hard work sometimes pays off in the end, but laziness ALWAYS pays off NOW.

Chris N

Re: Pact Ti fix
« Reply #4 on: 14 May, 2016, 01:55:00 pm »
It's a 73° seat angle and I'll be using an inline post and probably a 100mm stem with compact bars. I don't think that's too laid back, but it's certainly not a racy position I'm aiming for.

zigzag

  • unfuckwithable
Re: Pact Ti fix
« Reply #5 on: 14 May, 2016, 08:08:23 pm »
nice frame, well thought through, one of those "do-everything" bikes

Re: Pact Ti fix
« Reply #6 on: 15 May, 2016, 08:58:25 am »
Looks very nice.
Can I ask how you intend to adjust the chain for tension / wear?
The fork ends shown don't seem to give you many options.
Or am I missing something obvs?

rogerzilla

  • When n+1 gets out of hand
Re: Pact Ti fix
« Reply #7 on: 15 May, 2016, 09:55:13 am »
I think chris n is one of those people for whom an ENO hub works.  I found the thing constantly slipped round and lost tension, despite roughening the ends of the axle, buying longer bolts and really mullering them down.  I could get about 50-60 miles before the chain looked slack - this is after 106 miles and it's not quite right:

Hard work sometimes pays off in the end, but laziness ALWAYS pays off NOW.

Tim Hall

  • Victoria is my queen
Re: Pact Ti fix
« Reply #8 on: 15 May, 2016, 10:25:07 am »
Except he says the rear wheel is a Surly Ultra New hub.
There are two ways you can get exercise out of a bicycle: you can
"overhaul" it, or you can ride it.  (Jerome K Jerome)

Paul

  • L'enfer, c'est les autos.
Re: Pact Ti fix
« Reply #9 on: 15 May, 2016, 10:27:38 am »
I'm looking forward to seeing this.

Will it be raw, or painted?

What's with the exploded toilet?
What's so funny about peace, love and understanding?

Chris N

Re: Pact Ti fix
« Reply #10 on: 15 May, 2016, 02:08:45 pm »
The frame has adjustable dropouts to vary the tension. They're shown in the bottom left corner of the drawing. The the bottom one is the drive side moving plate, the middle is the disc side and the top is the bit that is welded into the frame. They're very similar to this one (though this is for an MTB through axle):



They pivot at the top of each plate and are clamped in place with two M6 screws. Total range of movement is about 20 mm. IMO they're the least worst solution to chain tension on a fixed disc frame.

Chris N

Re: Pact Ti fix
« Reply #11 on: 15 May, 2016, 02:10:26 pm »
I'm looking forward to seeing this.

Will it be raw, or painted?

What's with the exploded toilet?

Me too. :thumbsup:

Raw brushed ti. 8)

Nothing really, just thought it was a good exploded view.

Re: Pact Ti fix
« Reply #12 on: 15 May, 2016, 02:43:59 pm »
The frame has adjustable dropouts to vary the tension. They're shown in the bottom left corner of the drawing. The the bottom one is the drive side moving plate, the middle is the disc side and the top is the boy that is welded into the frame. They're very similar to this one (though this is for an MTB through axle):



They pivot at the top of each plate and are clamped in place with two M6 screws. Total range of movement is about 20 mm. IMO they're the least worst solution to chain tension on a fixed disc frame.
Oohh!
That's a bit cunning / clever. I was wondering what is going on there. Not seen those before. I'll be interested to hear how they work out.

Paul

  • L'enfer, c'est les autos.
Re: Pact Ti fix
« Reply #13 on: 15 May, 2016, 05:26:35 pm »
The frame has adjustable dropouts to vary the tension. They're shown in the bottom left corner of the drawing.

Cor - that's a busy back end. It looks strangely attractive.

Speaking of back ends:

What's with the exploded toilet?
Nothing really, just thought it was a good exploded view.

Something I ate/drank yesterday had a similar effect on our toilet this morning  :o
What's so funny about peace, love and understanding?

Chris N

Re: Pact Ti fix
« Reply #14 on: 16 May, 2016, 08:48:04 am »
Oohh!
That's a bit cunning / clever. I was wondering what is going on there. Not seen those before. I'll be interested to hear how they work out.

As far as I can tell, this is a variation of the swinger dropout originally designed by Black Cat Bicycles, then refined by Paragon and Salsa.  I've got the Salsa Alternators on my MTB, and they work very well indeed.  No problems with slipping so far.  I hope that these ones will be as good.

Chris N

Re: Pact Ti fix
« Reply #15 on: 16 May, 2016, 08:48:22 am »
Nothing really, just thought it was a good exploded view.

Something I ate/drank yesterday had a similar effect on our toilet this morning  :o

 :sick:

Chris N

Re: Pact Ti fix
« Reply #16 on: 17 May, 2016, 09:17:38 am »
Managed to wrestle some Challenge Strada Biancas onto the Stans Alpha 340 rims for this build without using tyre levers last night, so it'll have gumwalls instead of the Gravel Kings. Wheels are a bit heavy at 3.5kg for the complete pair (inc. QRs, discs, tyres and fixed cog) but they'll do. I don't think there's a much lighter solution without changing to a minimally spoked SON Delux dynamo. Fork, headset and seatclamp are scheduled for delivery this week sometime.

Chris N

Re: Pact Ti fix
« Reply #17 on: 21 May, 2016, 03:49:15 pm »
Boring pic of parts stockpile

 :thumbsup:

billplumtree

  • Plumbing the well of gitness
Re: Pact Ti fix
« Reply #18 on: 21 May, 2016, 09:14:03 pm »
Chain's a bit....

Chris N

Re: Pact Ti fix
« Reply #19 on: 20 June, 2016, 11:29:13 am »
Frame is done:






jiberjaber

  • ... Fancy Pants \o/ ...
  • ACME S&M^2
Re: Pact Ti fix
« Reply #20 on: 20 June, 2016, 01:19:14 pm »
Wow nice  :thumbsup:
Regards,

Joergen

zigzag

  • unfuckwithable
Re: Pact Ti fix
« Reply #21 on: 20 June, 2016, 01:37:27 pm »
very nice! purely from my personal perspective i would request the outer side of the back end of chainstays to be flush with the dropouts in order to avoid brushing/catching them with my heels (not relevant to the majority who pedal with their feet straight).

Chris N

Re: Pact Ti fix
« Reply #22 on: 20 June, 2016, 01:44:57 pm »
Wow nice  :thumbsup:

Thanks. :)

very nice! purely from my personal perspective i would request the outer side of the back end of chainstays to be flush with the dropouts in order to avoid brushing/catching them with my heels (not relevant to the majority who pedal with their feet straight).

Yes, good point.  It's a reasonably long back end, designed around a wide chainline (52mm) and I do pedal with my feet straight, so hopefully I won't catch the stays.  There's a lot of unknowns to me around the design - I hope I've not specced anything stupid, and that it all goes together smoothly.

Re: Pact Ti fix
« Reply #23 on: 20 June, 2016, 01:51:22 pm »
Lovely.... will those itty bitty allen bolts hold the dropout still against the rear wheel torque?  I've got an ENO hub and that has to be cranked down bloody hard to stop it slipping, and it's got a big bolty thing holding it tight.

Chris N

Re: Pact Ti fix
« Reply #24 on: 20 June, 2016, 01:56:18 pm »
I think they're M8 bolts, so I hope they'll hold the plates in place.  I can get some serrated washers to go under the heads if they don't.