New to me 2000 ST1100 - question re: re-jetting carbs for high altitude

COst1100rider

Joined
Apr 9, 2012
Messages
14
Location
Florissant, CO
Bike
2004 ST1300
Hi all,
Just bought my first ST1100 and it's been many years since I've had a bike with carbs. I bought the bike in Kansas City, Missouri and just rode it home to Colorado. I'm at 8800 feet elevation and wondered if I need to get the carbs re-jetted.

The bike seemed to run OK on the way home but did seem to lose acceleration the higher I got. Never backfired or anything but still wonder if I need to do anything.

What do you experts think? Anyone from Colorado with some personal experience? Let me know. Thanks.
 
COst1100rider said:
Hi all,
Just bought my first ST1100 and it's been many years since I've had a bike with carbs. I bought the bike in Kansas City, Missouri and just rode it home to Colorado. I'm at 8800 feet elevation and wondered if I need to get the carbs re-jetted.

The bike seemed to run OK on the way home but did seem to lose acceleration the higher I got. Never backfired or anything but still wonder if I need to do anything.

What do you experts think? Anyone from Colorado with some personal experience? Let me know. Thanks.
Click to expand...

Losing acceleration at altitude is partially due to the thinner atmosphere, even if you dial in the air-fuel mixture perfectly, so you're never going to recover all of that power loss no matter what you do.

I'm not from CO, so I'll just leave it at that.
 
I've never heard of anyone re-jetting an ST1100 for altitude. Besides, what would you do when you went to the lower altitudes?
 
Our 1100 runs well at altitude, I havent noticed any issues at all. Im kind of jealous knowing you live smack in the middle of such a great area for riding. We have a lot of Colorado folks on here and would love to see you on one of our Ride To Eats... See the Team Colorado thread to say hello to the locals..
 
Well I'm not an expert in this at all. I just know that a lot of people here re-jet their ATVs due to the altitude so I figured that might be something I'd need to do too. As far as going to lower altitudes - now that I'm home the vast majority of my riding will be here in the mountains. The lowest I'd probably be going would be to eastern Colorado which is still almost a mile higher than Missouri.
 
Don't screw with it. I owned a 1100 for many years here in Colorado and never had an issue with altitude. Had a lot of problem with attitude but never altitude:D Welcome to the forum. Come on over to Team Colorado Sub Forum. As said before, join us for the RTEs and some of the get togeathers. Also take a look at our Colorado Tag sub forum.
 
Thanks everyone for the advice. Sounds like I'll just leave well enough alone. Thanks also to the CO folks for the warm welcome. I'd love to get together and meet the folks from Team Colorado. Not sure how or where to introduce myself to the team.
 
One thing... run the lower octane fuel... the bike will do well with it and your wallet will appreciate it.
 
I'd listen to the voices of experience here, but for the record there is a High Altitude Adjustment procedure for continuous operation above 6,500 feet, page 5-16 in my Honda Service Manual. Basically you just screw in the pilot screws a ? turn. FWIW

John
 
I agree with ChucksKLRST. I live at 7544' and ride to Kansas, about 1800' and Montrose (Monarch Pass +12,000') and don't notice any negative issues. More of an issue is tire pressure. That will vary more than 3 lbs with the altitude changes, but, like the carbs, I just set it and forget it.

jim
 
John has it right on the 1/2 turn IN for the pilot screws. Takes a special tool and some fiddling to get'er done. Can't say it's worth the effort.

I've always noticed significant loss of power at the top of Trail Ridge Road (US-34, also called Ogden Avenue at the Chicago end. :D) Otherwise, no worries up to and including Leadville.

If yours is set a little more rich initially, turning those jets IN for less rich/more lean might give ya an incremental improvement. If you DON'T need choke at all when starting from cold, she's probably too rich. No need to re-jet in any case, the adjustable pilot jets have plenty of range...

Welcome to the site, and keep us poSTed on yur progress. And do hook up with the Colorado Crew, they're about the most active bunch on this forum...
 
You must log in or register to reply here.
Back
Top Bottom