10mm Red LEDs in bike flasher?

Hello All!
My 18 LED flasher is starting to get long in tooth after 4 years of use (longer than most of you guys use LEDs) /ubbthreads/images/graemlins/wink.gif Anyway, I was pondering modding a 5 LED flasher with those 7,500 mcd 60 degree 10 mm LEDs.
The 5mm LEDs put out 1,500 mcd max with the 10mm jobs putting out 5 times that. Granted, the forward voltage of the big'uns is 2.4V to 3.1V Max so that could lead to some problems. Here is my concept.
Use a 5 LED flasher that runs on 2AA batteries and run lithiums to boost the voltage to 3.4V. This will help when riding in the cold and have a brighter light longer.
To help the flasher transistor, I epoxy a metal heatsink on it to assist in cooling. Solder the 10mm monsters in and test one of them with my mA meter to see if it pushes them to at least 20mA. They are rated for 30mA so I assume that I can change the resistor to get it to 25mA or so.
Has anyone messed with the large 10mm LEDs and does my concept have any merit? Lithium juiced 10mm 5 LED flashers sure would help when riding in the cold months. If that works, figure out how to slap a 123a lithium in it to save a few bucks.
Any help would be appreciated. /ubbthreads/images/graemlins/smile.gif

Forgot the link to the LEDs /ubbthreads/images/graemlins/whoopin.gif
http://www.lc-led.com/View.jsp?idProduct=166

Why not just have a bare red LS on a flasher circuit. I don't think you'll even need a heatsink if the flashing rate is correct. /ubbthreads/images/graemlins/smile.gif

Nerd,
Yes, I could try that...I do have a red LS laying around. Not heatsinking it would be a bit problematic, the flasher can be kept constantly on. Now to go find the epoxy, a piece of aluminum and some solder.

Have some part of the aluminium in contact with air and heatsinking problem is minimised since when the bicycle is moving, the airflow would cool down the LS, even at low speeds. I'm thinking a heatsink from those old amplifiers my father has lying around... now to find a red LS, some duct tape.. hehe.. /ubbthreads/images/graemlins/smile.gif

I found red LS's are really great for back lights.
It's maybe slightly overkill, but I have 3 HD's, two bare & one with a 30° fraen lens.
They are only slightly heat sunk, but I run them at only ~300mA so heat isn't much of a problem.

Olivier