|
SuzukiSavage.com
/cgi-bin/YaBB.pl General Category >> Rubber Side Down! >> Changes for higher elevation? /cgi-bin/YaBB.pl?num=1198460138 Message started by Stimpy on 12/23/07 at 17:35:38 |
|
Title: Changes for higher elevation? Post by Stimpy on 12/23/07 at 17:35:38 I know I've seen a thread about this topic somewhere but I just couldn't find it, so my question is: What needs to be done to the carb/jets/air filter/exhaust/spark plug? for correct operation at 8000 feet (2500meters) above sea level? Currently running flawless (perhaps a bit rich) at sea level in SoCal. What is the basic theory on internal combustion with less oxygen in the atmosphere? Thanks in advance. RP |
|
Title: Re: Changes for higher elevation? Post by barry68v10 on 12/23/07 at 18:33:04 Less fuel needed for higher elevation because of less O2. Smaller jets, more space on the needle valve, etc. will help you maintain the correct air/fuel ratio at high altitudes... |
|
Title: Re: Changes for higher elevation? Post by barry68v10 on 12/23/07 at 18:34:26 Oh, and your final detonation pressure will decrease and the flame-front will burn slower, so less octane is needed. |
|
Title: Re: Changes for higher elevation? Post by Reelthing on 12/24/07 at 06:05:48 Interesting read on it for Bing carbs.... the HP chart is also interesting http://www.horizonsunlimited.com/tech/carbjet.shtml |
|
Title: Re: Changes for higher elevation? Post by thumperclone on 12/24/07 at 07:09:41 in western colorado im at 4500' ,ride up and over 10,000' couple times a year or so, have had no issues(some bf on quick decell) with this set up on my 06.. 3" hard krome slash cut w/ spiral steel baffel,k&n drop in de snorkeled air box,stock ngk plug,# 60 pilot,141.3 main,have dyno jet needle 2nd slot from top..adv 50 mpg,plug color perfect, regular unleaded gas... hope this helps.. |
|
Title: Re: Changes for higher elevation? Post by Reelthing on 12/24/07 at 07:33:59 141.3 main? might a been off one key on the keyboard - bet thats a 152.5 ? |
|
Title: Re: Changes for higher elevation? Post by strangeling on 12/24/07 at 08:56:14 Stimpy, Where are you going or moving to ? |
|
Title: Re: Changes for higher elevation? Post by thumperclone on 12/24/07 at 09:03:00 0334343D2539383F36510 wrote:
had a dyno #145 main = mikuini?? had stealer do the tuning(was the 4k service) they got a tuning meter of some sort tech wrote 141.3 on job ticket..dont sound right to me either |
|
Title: Re: Changes for higher elevation? Post by Reelthing on 12/24/07 at 10:21:43 Oh! a dynojet - if our old chart is correct that would be pretty small - is your 60 pilot a dynojet size as well? http://suzukisavage.com/cgi-bin/YaBB.pl?board=tech;action=display;num=1104263751 Mikuni / Dynojet Size Comparison Chart Mikuni--Dynojet 140-----149.3 150 142.5---152.0 145-----154.7 edit: so mutter mutter..... between a 135 and a 137.5 mikuni - but the shape of the dynojet is a little different - might increase the speed the gas moves through the jet |
|
Title: Re: Changes for higher elevation? Post by vtail on 12/24/07 at 10:47:41 Your carb (standard mikuni) is altitude compensating. IAW as you go up in altitute it leans itself. The slide get pulled (sucked) up by the amount of difference in airpressure above the rubber diaphram vs below. As you go up in elevation you get less of a pressure difference between above and below the diaphram so it does not pull the needle up as high. The needle, being tapered allowes less fuel to get sucked thru the jet so the mixture stays fairly constant. The ideal being about 14:1. I've been over the Berthau Pass in CO (over 11000 ft) with a Bing eguipped car without a problem and have flown Bing carburated lightplanes to 18000 ft without changes. So I wouldn't do anything (maybe a mixture screw and idle adjustment) unless you were going to be living at that elevation. If your bike has over 20000 miles I would put in a new jet and needle since there is a slight amount of wear on both which would enrich the mixture. Also would be good to clean the slide and bore from deposits for smoother operation. ;) |
|
Title: Re: Changes for higher elevation? Post by Stimpy on 12/24/07 at 11:50:22 Quote:
Loooooonng story, but basically after living in the Baja/San Diego area all my life I moved to Germany 10 years ago, then I came back 2 years ago and now I may be moving to Mexico City for a while before going back to Germany permanently. I was going to sell the bike here but I've decided to have it shipped to MexicoCity so I can use and eventually sell it over there, oh man! it's really gonna hurt when the time comes to sell it. Thank you all for your input, it seems that with a good carb cleaning & smaller/stock main jet (currently 160 main) the bike should be running fine "up there". Happy holidays :) |
|
SuzukiSavage.com » Powered by YaBB 2.2! YaBB © 2000-2007. All Rights Reserved. |