Question for you exposed motor sno bikers
- Thread starter rmking700
- Start date
Over fueling on the EFI bikes from low engine temps.
unless you never do more than trail riding hard pack its not even a question of whether or not its needed. absolutely
use a temp guage and you can watch temps drop from 180 to below 100 in under a minute if fresh powder. if you jump on cold motor and just pin it then your the guy that dont need a engine cover............
use a temp guage and you can watch temps drop from 180 to below 100 in under a minute if fresh powder. if you jump on cold motor and just pin it then your the guy that dont need a engine cover............
that's only on some models. The sx 450 race bikes have manual choke so the motor wont over fuel, am I missing something?
I ran a motor cover last year for part of the year . I had to loose it. More issues with overheating than too cool. Unless I was constantly in bottomless powder. But that is not realistic on every ride. This year I may try cover the motor again but am going to run a heat exchanger.
Sent from my iPhone using Tapatalk
Sent from my iPhone using Tapatalk
I ran avid carb heater and had no carb icing. On deep days snow hitting the pipe would cause a bog. Going to need to come up with an engine cover as running temps were lower than I would like them. Running a different bike this year so not sure how it will be different
I ran my cr500 in Utah and never had an issue with an exposed engine even in the deep... Used a carb heater and stat... But I make sure that I only use the carb heater when the carb freezes... With a shut off valve.. it would still be hard to get the bike above 90 in the deep though.
Sent from my XT1585 using Tapatalk
Sent from my XT1585 using Tapatalk
R
Rush44
Well-known member
Aluminum block + snow = cold motor. You have to cover it... a stat will help build temps back up quicker but it doesn't do much to stop the steep drop during pow days. Like other have said you can literally watch your temp gauge dive from 180 to 120 in about 20 seconds when blowing through deep champagne. FI bikes will compensate the cold air temps with more fuel and combine the lack of heat for the rings to properly seal and you get blowby... fuel in the oil. Use an engine cover + stat + temp gauge if you really want to keep the bike running well and fuel out of your oil.
I hear what your saying, It wont overfuel like an auto choke engine will however the temp sensor which monitors fresh inlet air will richen mixture, surely a map can correct that and prevent overfueling due to cold inlet air?, and there is no exhaust temp sensor on the race bikes, trying to get to the root of the problem instead of masking the real issue. many thermostats have a huge bypass hole that always circulates some water through the radiators, some almost shut off completely, looking into that as well,I hear about many covering the radiator with plastic, That is a bandaid and means the t stat is allowing too much flow all the time thoughts?
Last edited:
R
Rush44
Well-known member
Yes, remapping the bike can compensate for what the stock ECU sends from the intake temp sensor probe. I've used Dobeck Gen4 AFR+ in the past and have had great results in getting the right AFR no matter what the ECU tells the bike. Thermostats like the Thermobob TB3 or Avid completely close off the bypass loop until temp is achieved, so you won't have a cold stream of coolant flowing into the motor during the warmup period.
I know the avid stat is a complete shut off... That is what I use... Still the powder does suck the warmth out.
Sent from my iPad using Tapatalk HD
how much cover is needed if the t stat really closes ,have any pics or suggestions? putting foam between the skid plate and bottom of cases will keep cold snow from getting in cooling down oil as one precaution?
R
Rush44
Well-known member
I've been doing the closed cell foam between skid plate and sump with no shielding for the last few seasons... it helps but it is not enough for deep powder.
looks like you in a very cold area . all good info Thanks
Opinions on available shrouds
So who's running any of the shrouds available out there? (not homemade) The ones i can find are moto 365, PST on thermobob's website, and the SXS snowshed plate.
None of the websites have great pictures. So far i like the look of the pst because from what I can tell, it looks easy and quick to remove. Anyone with real world experience want to chime in?
So who's running any of the shrouds available out there? (not homemade) The ones i can find are moto 365, PST on thermobob's website, and the SXS snowshed plate.
None of the websites have great pictures. So far i like the look of the pst because from what I can tell, it looks easy and quick to remove. Anyone with real world experience want to chime in?
Moto365 and SXS are the same. What bike do you have? I'll try to get some pictures of it for you.
sx450
Not the best shots of it, I'll try to update with some better ones next week. I don't have anything installed at the moment though, so stuck with old pictures.
Last edited:
Gotcha. Sorry, camping this weekend-just found good service. Picked up a 16yz450fx with 5 hrs on it. Thanks for the pics!
