what jet to start with?
- Thread starter Jeff Bennett
- Start date
please go educate yourself on the effects temperature and altitude have on air density and pressure, and how that effects oxygen content and jetting, it's basic tuning principles anyone giving advise should already know ha ?
if you think the oxygen content is the same at sea level as it is on Mt. Everest you must have missed that day of school ?
the Op posted it was 30 F in his post, it's 20 degrees F here today, thats fahrenheit not celcius.
thats colder than it's ever been where you live.
if I came to 85' elevation and average low temps of 6 C, I might ask you for jetting advice,
but i doubt it
my advice was to buy 270 thru 310 jets, start large and plug chop down.
thats advising a safe jetting range, promotes learning to plug chop down, allows them to order a range of jets all at once to save on shipping costs, and have a couple extras for future mods and/or changing enviroments.
my personal experience in these temps with that pipe/mods say a 310 will be very close, and definately safe !
(again....we run 290 main jets in summer temps w/ that pipe/mods @ similar elevation)
for anyone to suggest 1 main jet size like you did is just plain ignorant.
I live, ride and successfully jet multiple machines in this enviroment, I know what it takes for a bike to survive in it.
If you or your buddy thinks that makes me a king, I'm flattered
you may want to rethink that from what i'm seeing
One thing I have learned from my experience is that once you hit 7000 feet, temp and humidity play a much more significant role.
I was on one ride last summer where elevation changed a bit over 2000 feet during the ride. and temp fluctuated almost 25 degrees. I ended up changing jets 4 times that ride. This is the ride I hit 9200 feet. I didn't stay at that altitude long. If I had trouble breathing I figure my baby did too.
I stared at about 7000 with a 270. at 9200 it was at a 240. I had a dmc, filter and no lid.
I was sure the -1 jet size/2000 feet of elevation rule was a good one. I had to drop 3 jet sizes in that last 2200 ft. Blew my theory out the window.
I was on one ride last summer where elevation changed a bit over 2000 feet during the ride. and temp fluctuated almost 25 degrees. I ended up changing jets 4 times that ride. This is the ride I hit 9200 feet. I didn't stay at that altitude long. If I had trouble breathing I figure my baby did too.
I stared at about 7000 with a 270. at 9200 it was at a 240. I had a dmc, filter and no lid.
I was sure the -1 jet size/2000 feet of elevation rule was a good one. I had to drop 3 jet sizes in that last 2200 ft. Blew my theory out the window.
good info man, based on personal experience !
you say temps fluctuated 25 degrees.... between what and what overall summer temps ?
I only ride a 6-700' elevation change daily, but just jet a little rich for the leanest situation @ 1800',
as long as it's not fouling plugs @ 2400'....run it, been working for years.
I can do that elevation change in 10 minutes, so there's no time to be stopping to rejet, or i'd still be up there
I have gone from those alt's down to sea level once, but forget how much richer i had to go.
I can't wait to ride at sea level. Haven't had a blaster out of the clouds since I was a kid.... damn since 89.
So Jeff I hope all us 5 year olds were able to accidentally give you some good advice.
So Jeff I hope all us 5 year olds were able to accidentally give you some good advice.
LOL, you guys are cool! BTW, all of you here have gave me good advice. I would definitely want to be rich rather that lean. Just wish I could find some jets around this state! I should have the cylinder back today so I will be able to heat cycle it with the 230, I guess, but I cant ride until I get some jets. Do they need to be genuine mikuni?
yeah make sure they are genuine mikuni. off brands do not always have the same bore and some have been known to be off center.
Maybe a member might have some multiple jets they would be willing to donate. If I had any extras, I would send some out. If not, maybe you can try www.jetsrus.com
I have a box of jets. Let me see if I have the ones you will need. Actually a couple came from Dave ^^^ above so I am more than willing to send you few if I have them. Let me know.
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I need somewhere between 270-310 not sure exactly yet. It came with a 230 and I would say that was way too lean. I actually bought some jets off a guy on xs11 forum for my xs1100 and he mailed them to me in an envelope and the sorter and one of the post offices pushed them out of the envelope and they were lost somewhere.
well, last night I noticed that the neighbors dog has drug trash all over our yard. I went to start the wifes car a minute ago because it is 19 degrees here and still dark. Well, I was looking at that trash and noticed my cylinder was laying there in a plastic bag and a little box beside it. The ups man left my package laying somewhere outside and the dog tore it up. My top end gasket kit was there also. I couldn't find my nuts and washers and got my flashlight and they were all lying together. Guess I got lucky the dog didn't chew any gaskets up. I had sent the cylinder with the reeds still attached. Ken took them off to bore and hone it, my question is, all of the reed valves are completely shut except for one, it is slightly not sealed. Will this matter? I don't know if they are supposed to be closed completely or not. It don't look bent or crinked but you can see its not sealed like the other 3. Thanks.
It should be ok, but if you have a start problem, you'll know where to look. Might just try flipping it over see if it seals tighter.
It's bad enough that I have to worry about UPS, FedEx, and USPS doing their jobs. Now Fido is tearing my boxes up.
LOL, Ken, at least you do your part well. The dog didn't hurt anything and I am glad the cylinder was in that plastic bag. I can believe he didn't chew the gaskets up. By the way, is there other bikes that these jets fit? I am sure others have our carbs. Maybe I could call another shop, like the Honda shop to see if they have jets for that carb.
