Designing a custom frame

Hi all,

I am 80% sure of buying a custom HT frame. It looks like it’ll be titanium. The frame needs to be able to do quick XCing and be able to descent pretty well to. In comparisment, my current Dekerf Team SST is a quick XC bike but descending isn’t it’s best thing.
I do not want a race bike but more an AM bike with at least 5” of travel. I want the rear to be quite forgiving. Cheers has already given me the tip of the height of my BB and I am thinking of ISCG mounts. I have already thought of adding some crud catcher bolts and leaving the water bosses out on the seat tube.

What tips do you guys have for me when designing a custom frame? I am really looking forward to your feedback!

forward facing seat tube clamp gap thing.

disc brake tabs - though probably a given since it's an AM rig.

cable stops to be larger to run full length hosing.



rear stays to have clearance for big tyres. 2.4" or so.

horizontal dropouts - i just like that.

Its an interesting thing to do for sure - I spent many hours reading up on what effect different angles had etc and became a bit over obsessed by 5mm here and half a degree there. Its all a careful balance between climbing / descending ability / handling and comfort. In the end though you will have something that you had a hand in designing and thats a great feeling when you're out on the trails riding.
One thing I did on my frame was to make the top tube the same diameter as the down tube - I reckoned this would allow the frame to cope with a long (4-5") travel fork without adding extra gussets.
I also left the bottle mounts off the seat-tube to let the seatpost drop down completely when I feel the need.
Good luck and be patient, better to wait a while now making your mind up than regretting something later.

jimjim2012":3kcfg7cb said:

forward facing seat tube clamp gap thing.

Click to expand...

That is a good one thanks!


When it comes to materials, lengths and angles, I am letting the builder do his work. He has 20+ yrs experience so I assume that'll work out fine.

I'll be very interested to see how you get on.

I kinda want the moon on a stick. I want the springy lightness of 90's steel XC bikes, I want it chuckable, fun and confident on the rough stuff, but not overkill hardcore, so AM is the right thing over full on FR, but how different is AM to XC really, tough XC frame 5" forks with a lil sag, medium weight bits, or actual AM/FR frame, or custom! Problem is I need to sample a lot of bikes and do a lot more riding before I know exactly what I want and how big, so spending on a Ti custom, or steel custom would be a bit nuts right now. Saying that the off the peg frames are £300-600 anyway in steels, and On-One Ti's were selling for £799!

keep researching and looking at features and sizes you like I guess.

Can you get to try out some bikes? Like hire them at trail centres. Maybe even consider trading a few that reportedly do what your after, see what you like and dislike. FWIW I think Cotic's and Dialled bikes have the kind of thing your looking for and I believe 18Bikes have something similar in the pipeline. You could try to try them or at least read the design features.

Hi Kaiser. Thanks for your reply. Dialled bikes have their Alpine. I have one as well. I also have a 07 Rocky Mountain Slayer, 07/08 Dekerf Team SST and a no name honky tonky taiwanese Ti frame.

I am pretty sure of what I want. I reckoned that 2 know more than 1 and was wondering if I could learn from other's pitfalls like the BB height or the seatpost sleeve/slide thingy in the front.

That sort of thing.