Fitting gear shifter on tt frame

IF YOU ARE HANDY ...

[INDENT]FIRST, you need to cannibalize the receiving post from a (vintage) clamp-on downtube shifter ...

THEN, you will want to fabricate a DIY strap which will replace the original strap ...

[INDENT][INDENT]Make a template from a manila folder OR whatever material is handy for you to use ...

Figure out where you will be "folding" the strap & (especially) where you will drilling the hole which will receive the post ...

CONSIDER installing an auxiliary steel washer between the strap & the post's base ...[/INDENT][/INDENT]

[INDENT]You will ALSO want to epoxy a small "stop" on the frame's downtube which is effectively a cleat which will keep the DIY strap from slipping down the downtube!!!![/INDENT]

Depending on your sensibilities, you can use EITHER a 12" piece of brass stock (¿ 3/8"-to-1/2" wide ?) OR cut-and-fabricate a strap from a large tin can (!?!) ...

[INDENT]Round the corners & coin-and-debur the edges!!!

Secure the ends by mimicking the standard clamp.
[/INDENT]
PAINT the DIY strap if you use almost any type of steel ...

DONE!!

[/INDENT]

alfeng said:

IF YOU ARE HANDY ...

[INDENT]FIRST, you need to cannibalize the receiving post from a (vintage) clamp-on downtube shifter ...

THEN, you will want to fabricate a DIY strap which will replace the original strap ...

[INDENT][INDENT]Make a template from a manila folder OR whatever material is handy for you to use ...

Figure out where you will be "folding" the strap & (especially) where you will drilling the hole which will receive the post ...

CONSIDER installing an auxiliary steel washer between the strap & the post's base ...[/INDENT]
You will ALSO want to epoxy a small "stop" on the frame's downtube which is effectively a cleat which will keep the DIY strap from slipping down the downtube!!!![/INDENT]
Depending on your sensibilities, you can use EITHER a 12" piece of brass stock (¿ 3/8"-to-1/2" wide ?) OR cut-and-fabricate a strap from a large tin can (!?!) ...

[INDENT]Round the corners & coin-and-debur the edges!!!

Secure the ends by mimicking the standard clamp.
[/INDENT]
PAINT the DIY strap if you use almost any type of steel ...

DONE!![/INDENT]

Thanks but not sure what to make of your suggestion! is there not a version I could buy!!

Well ...

[INDENT]If you think about it, there isn't a standard down tube size for TT bikes ...

[INDENT]So, while it isn't impossible for one to exist, I think it is implausible to expect an off-the-shelf "clamp" which will allow an individual to use a down tube shift lever since YOU are possibly the only individual who wants to use one on his/her TT bike.[/INDENT]
[/INDENT]
So, just exactly WHY don't you want to use the companion, front shifter for your triathlon bars?

alfeng said:

Well ...

[INDENT]If you think about it, there isn't a standard down tube size for TT bikes ...

[INDENT]So, while it isn't impossible for one to exist, I think it is implausible to expect an off-the-shelf "clamp" which will allow an individual to use a down tube shift lever since YOU are possibly the only individual who wants to use one on his/her TT bike.[/INDENT][/INDENT]
So, just exactly WHY don't you want to use the companion, front shifter for your triathlon bars?

you are right of course. its a TT bike I built up from ebay as only do 1 or 2 TT's a year. I don't have a front shifter for tri bars and only need small chainring for warming up/down. I like the simplicity & look of it on downtube also. anyway it seems I need to go down the conventional route and put one on the tri bars.
cheers for your thoughts

OKAY!?!

[INDENT]IF the seat tube on your TT frame is ROUND or the actual seatpost is ROUND ...

[INDENT]THEN you may be able to clamp a "traditional" downtube shifter clamp onto it.[/INDENT]

You will need to figure out WHERE you can mount it so that it doesn't intrude with either your foot or your leg ...

And then, you will PROBABLY want to add a "CLEAT" (i.e., EITHER epoxy a small tab OR insert a screw which has a reasonably large head ... OR, you may be able to simply use a piece of old inner tube between the frame & clamp) which will keep the clamp from slipping down the seat tube.

[/INDENT]