• Don't miss out on all the fun! Register on our forums to post and have added features! Membership levels include a FREE membership tier.

Question about thermostats?

R
Jan 28, 2018
21
1
3
68
Why do the thermostats for two strokes come in the 130 to 140 degree range but the four stroke thermostat are in the 170 degree range? I have two on the shelf, one for a carb heater from Avid and one for a set of Raze heated handlebars.
 

wwillf01

Well-known member
Lifetime Membership
Aug 12, 2012
2,790
616
113
44
Heber Ut
Why do the thermostats for two strokes come in the 130 to 140 degree range but the four stroke thermostat are in the 170 degree range? I have two on the shelf, one for a carb heater from Avid and one for a set of Raze heated handlebars.


Those are where the engines run better temp wise. That being said I have ran a 2 stroke with the 170 and it has been fine because I use raze handlebars.
 
M
Jan 14, 2004
3,078
1,390
113
The FI 4 stroke likes to be over 170 degrees which keeps it from going into the cold loop ie: 5:1 AF ratio and over fueling the bike which also cools the bike down, double bad. Carbed 4 strokes don't care as much as the fuelies. 2 strokes seem to max out power wise at about 120 degrees, there are no over fueling concerns though. There is no substitute for a good temp gauge.


M5
 
Premium Features