pebiker
XS650 Member
Do I raise the clip to lean, or do I lower to lean
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daroberts3
XS650 Addict
Move the clip towards the top of the needle to lean out the midrange. Tons of info in the tech section about carb. tuning.
manofsteele
XS650 Addict
Actually you lower the clip which raises the needle letting more air in.
manofsteele
XS650 Addict
Yeah, yeah that's what I meant, lol
angus67
Welder's penetrate deeper!!
agreed.........
bluebikerblan
Geezer
What 5twins says......as usual. Blue
Welcome to the forum pebiker. pe huh, gym teacher?
Sounds like you need to read www.amckayltd.com/carbguide.pdf Not only read it but print it out, the you can take it with you and read it. Read it till you understand it.
Leo
Sounds like you need to read www.amckayltd.com/carbguide.pdf Not only read it but print it out, the you can take it with you and read it. Read it till you understand it.
Leo
pebiker
XS650 Member
You guessed it, I do have the carb guide , but really till you do it for yourself the guide is just words on paper. All I wanna do is get this thing runnin the best it can. Right now I got a 79 XS650 with 135 main and 27.5 pilot jet and the needle is on the second slot from the top. Homemade pipes with mikesXS pods and B8ES plugs which just fouled out. That's why I asked the question about leaning out the carb. If I lean the needle, will I need to go to a 30 on the pilot jet? Also the cold temps in Ohio make jetting very tough. Thanks all for your help.
First, you're using the wrong plug, both type and heat range. You should have a BP7ES in there. The "BP" means it's a projected tip type and the #7 is one step hotter than the 8. That cold #8 plug is probably contributing to the fouling.
The 135 main and 27.5 pilot are the stock sizes. They will need to be stepped up one or two sizes on both, maybe even a bit more on the main. The needle in the #2 slot is already leaned a step, leave that be if you increase the other jets. If you don't for a while, put it back in the stock #3 (middle) slot.
The 135 main and 27.5 pilot are the stock sizes. They will need to be stepped up one or two sizes on both, maybe even a bit more on the main. The needle in the #2 slot is already leaned a step, leave that be if you increase the other jets. If you don't for a while, put it back in the stock #3 (middle) slot.
For intial tuning using BP6ES plugs will help prevent fouling. Just to get it a bit closer, don't use them for high speed testing or for very long at lower speeds.
The temp can effect tuning. With a temp below 50 or so you tend to have coughs that you don't get at higher temps. Colder leans things a bit.
Mike's pod filters have the same problem the K&N's that they copy have. The shape has air flow issues that CV carbs don't always like. An of idle stumble that is hard to tune out.
He does sell a long straight walled K&N that will work better. Item # 15-0510
I have Uni Filters on mine. Don't recall the model number. They have the double wall foam. Layer of black inside, layer of red on the out side.
I don't have the off idle stumble any more.
The stumble wasn't hardly noticable. Just enough to notice if you were paying attention.
Just enough to be aggravating.
Leo
The temp can effect tuning. With a temp below 50 or so you tend to have coughs that you don't get at higher temps. Colder leans things a bit.
Mike's pod filters have the same problem the K&N's that they copy have. The shape has air flow issues that CV carbs don't always like. An of idle stumble that is hard to tune out.
He does sell a long straight walled K&N that will work better. Item # 15-0510
I have Uni Filters on mine. Don't recall the model number. They have the double wall foam. Layer of black inside, layer of red on the out side.
I don't have the off idle stumble any more.
The stumble wasn't hardly noticable. Just enough to notice if you were paying attention.
Just enough to be aggravating.
Leo
pebiker
XS650 Member
Thanks for the info. I did not know about the plugs. Next question would be; Is this why the stock jets appear to be too rich ( cause the plug is too cool)? I will next try the 140 main and the 30 pilot with the hotter and correct plug.
Yes, the colder plug will burn darker and give the appearance that you're too rich. The other important setting you must get right on these carbs is the float level. If it's off and the fuel level in the bowl is too high, the bike will run rich regardless of what jet sizes are in there.
pebiker
XS650 Member
I appreciate all of the help with this. Lots of good ideas and I have everything I need to make the suggested changes. I will let you all know how it turns out.
Any good on-line site to buy the uni-pods? Thanks to all for their time and the help.
The ones you want for your 38s are UNI part #UP4200 or UP4200ST (dual layer). They have a 2" I.D. mounting flange and are 4" long. I got mine here .....
http://www.motorcycle-superstore.com/2/9/427/7841/ITEM/Uni-Air-Filter-Clamp-On-Pod-Filter.aspx
A note on oiling them. The black foam used on these is very fine. The regular foam filter oil will clog them. Use a 50-50 mix of plain motor oil and gas. I bought a cheap bottle of straight 30wt. at Walmart to use. They actually look better than that photo on the web site depicts .....
http://www.motorcycle-superstore.com/2/9/427/7841/ITEM/Uni-Air-Filter-Clamp-On-Pod-Filter.aspx
A note on oiling them. The black foam used on these is very fine. The regular foam filter oil will clog them. Use a 50-50 mix of plain motor oil and gas. I bought a cheap bottle of straight 30wt. at Walmart to use. They actually look better than that photo on the web site depicts .....
pebiker
XS650 Member
Just an update, tried the new spark plugs, reset the float on the right side and lowered the clip to the middle. Good weather in Ohio this week and the bike is running great. Thanks 5twins and XSLeo for all the help.
