Avid Carb Heater Install - CR500

[kell8071]

The best way to run a carb heat line is off the back of the cylinder on the 89-2001 cyl. There is a flat plate that used to have a fitting on the earlier 500's. Drill and tap it and it keeps your line super short to your heat flange. Even if the engine gets to 80F the venturi has been free of ice.

I'm planning to do this in the next couple days. How thick is the casting on the flat spot? Enough to drill & tap for 1/8" npt and have a good seal? I was thinking a little hondabond for good measure.

Kell

 

[M5-]

Its plenty thick for that fitting, that's how mine is done. with this system you always have heat available. Before I had carb heat my slide would freeze wide open and I'd have to hit the kill switch, not a real fun time. IMO freeze up is more likely in relatively higher humidity situations and the right ambient temperatures rather than snow conditions.



M5

 

[CATSLEDMAN1]

carb heat

I have tried several carbs on my WR450 and built carb heaters to match very similar to the AVID products unit. Although I haven't had carb icing issue when they were in use, it appears to me that while you bring heat to the carb, the block of aluminum heater itself sucks off a lot of coolant heat. I have tried several ways , carb boot out of neopreme, block of soft foam, etc to keep everything warm.

On my YZ250 I just wrapped copper tube around my carb bell in two loops and ran coolant through it. While more crude in execution it has proven as effective if not more effective on a bike more prone to carb icing.

 

[SEOINAGE]

Its plenty thick for that fitting, that's how mine is done. with this system you always have heat available. Before I had carb heat my slide would freeze wide open and I'd have to hit the kill switch, not a real fun time. IMO freeze up is more likely in relatively higher humidity situations and the right ambient temperatures rather than snow conditions.



M5

After my broken cable froze up I installed a tether, hopefully it saves me if I ever do have my slide freeze.

 

[jethro450]

In utah I have seen 4 and 2 strokes freeze... Now letting it idle does free it up in some cases.. Or you can enclose the carb so it catches engine heat... 90 percent of the time not an issue but for the other 10 percent it sucked...


Sent from my iPad using Tapatalk HD

It sucked bad

 

[kell8071]

Its plenty thick for that fitting, that's how mine is done. with this system you always have heat available. Before I had carb heat my slide would freeze wide open and I'd have to hit the kill switch, not a real fun time. IMO freeze up is more likely in relatively higher humidity situations and the right ambient temperatures rather than snow conditions.



M5

Yep my slide was freezing and unfortunately the kill switch was working intermittently! Scary stuff but I'm hoping this will help.

Agreed on the humidity though, some of my worst freezing has been on warmer but wetter days.