I just purchased an Arctic Cat 650 H1. How important is it to have efi (electronic fuel injection)? Is it true that my machine will have problems at higher elevations if not tuned? I live in Las Vegas and most my riding will be anywhere from sea level to about 3-4000 feet. However I will be taking it sometimes to much higher elevations, maybe near 8-10,000 feet. Will my machine still perform well? Should I invest in a carburator compensator? Anyone have any thoughts or experience on the matter? Would appreciate some feedback. Thanks

 

Well EFI is nice and helps fuel economy, but it is expensive. I live at sea level and I ride as high as 7000 feet. This weekend we are going camping/quad riding. The camp is at 5100 feet, low elevation in the area is 4400 feet. Been there many times and the biggest problem is the engine will load up a bit at prolonged idle, so we don't do it. Other than that the things run fine up to about 6000 feet. You shouldn't real have any issues with the 4000 feet. You can always get a Dial-a-Jet and that lets you change your jetting without having to open the carb up. I know a couple of guys who use them and have had really good results. So far I haven't felt the need to.

 

Depends on whether you just want to get by, or have it run the best it can.
The main advantage to EFI is that it is automatic, if you jet your carb for 10,000 feet, it will run about the same as EFI at 10,000 feet. Even with EFI or correct jetting, you lose about 3% of your HP for every 1000 feet.
So at 10,000 feet you have lost enough HP that your clutching will be off quite a bit also.

I live at 1000 feet and have been riding dirtbikes and ATVs at 8000 to 14,000 feet for over 20 years and always jet and clutch for best performance. I seen quite a few guys try it without rejetting with mixed results. Depends on whether you are jetted correctly or lean at seal level. It is common for ATVs and dirtbikes to come from the factory on the lean side to help pass emission tests. That is why lots of guys buy aftermarket jet kits to get correct jetting at low altitude.

 

The A/C isn't fuel injected? I've ridden carb'd quads from sea level to 6-8000 feet and the only problem is an occasional sputter, but nothing really bad. My buddies piped and jetted yfz450 sputters a bit more and seemed to be a little more sensitive to the elevation then my Rincon did.

 

Only the AC 700 is EFI

jcride, you will be fine. 4-strokes are a lot better then 2-stokes when it comes to elevation. What you will notice the most is the decrease in gas miledge.

 

EFI is really nice for starting up, (no messing with the throttle), and they dont require jetting, but if you jet your carb it will run just as good at higher elevations.

 

Have you ran your 650H1 with low altitude jetting at 10,000 feet and had it run just fine?
I don't know about the Cat 650, but I have seen some pretty poor running ATVs in Colorado that didn't jet for altitude.

 

No, not my H1. However my 2004 400 I had when I was in Alaska and ran that at sea level then a couple thousand feet above and didn't have any problems. But no, I haven't taken the H1 anywhere near 10,000.

 

Big difference in a couple thousand feet and 10,000 feet.
My 500 Cat takes a 127.5 jet in Colorado vs a 140 stock.
That is a big change to go without and hope it will run just fine.

Guess that is how you get around 4000 posts in a couple years,
answer every question whether you know anything about it or not.

 

I had my H1 up at 7780ft (gps highest point) and it seemed to run fine, there wasn't as much snap as lower down but it still whipped the king quad and rincon that were with me (in the mud only though)