How lean to go

[Paul Kelly]

need some help with this one

took my carbs apart to clean and noticed some burnt parts. specifically the little upside down clover on a stick dohickey that sits above the needle and is secured by a circlip. I have no idea what these things are called or what they do. Can anyone clear this up for me. I notice that they cover a hole in the top of the slider. Do they affect fuel delivery. I'm still running rich with 105s

[Paul Kelly]

Thanks

By the way thanks guys for all the input. This is a great site.

[Roostabunny]

By the way thanks guys for all the input. This is a great site.

I get my plugs at Carquest. You have one of those in Woodstock.

http://carquest.know-where.com/carquest/cgi/region?all=true&country=CA&region=ON&design=default&lang=en&option=&mapid=NorthAmerica#list

I second the comments on the dealership. Not very good service. With bikes this age it's tough. I always come to GSR first - that way you know when the kid at the parts counter is BS'ing you.

[Paul Kelly]

In between a rock and a hard place

I'm really struggling with this carb mix crap. Haven't ever had this much trouble getting the mix right before.

I'm down to 102.5 main jets and the needle is in the stock position. Bike is still running rough.. it idles ok and seems to run lean and rough. if I pull a little choke on it smooths out. obviously mix is too lean... right... but

If I put 105s main jets in the bike runs way too rich...needle has been leaned right out.

any suggestions guys.

[SAN]

how lean?

Hello, some of these members do not read every thing you ask before reply. but they try.sounds like if it was me "wich they will tell you im wrong" rebuild kits are recomended with age and miles. then start over with stock jets. and check petcock for leak. sounds like your choke rod is not closing all the way try pushing it in more with thumb. or its blocked. and my mac is just a steel baffle and sounds awsome.check out the 850 carb rebuild in this site or hire it out. let me know.SAN

[Paul Kelly]

Need direction

So guys, I've tried to re-jet my GS1000GL which has a 1083 big bore kit in it with a stock air box and a Mac 4 into 1 header with Mac muffler.

My approach has been all wrong up to date. I've recently read an instruction posted on this site which is..find the jet the bike runs on best in the 7-9k rpm range and then proceed to set the parameters for the mid and low ranges...makes sense.

So in using this method I'm going richer again, moving up from 105s in the main jets...here's my problem..to get the bike to rev past 5-6k in the driveway I have to pull the choke slightly (with 107.5s in) and the needle in the 2nd ring from the top (lowered) position.

Once I'm in the zone 7-9k bike pops and farts. Does this mean I'm too lean? This is happening when the engine is not quite fully warmed up.

I figure there is no point in road testing the jetting until I can at least get the damn thing to rev in the drive. Can anybody help? Much appreciated.

[robertob]

Revving in the drive won't really tell you much because there isn't a load on the engine.

Some of the more experienced guys will chime in but I suspect you will find the stock jets will be very close with a big bore kit and the stock airbox with no mods.

Ask "Salty Monk" on here what he used when he had the stock airbox and 4:1 pipe. I think it would be a good starting point for you.

[Paul Kelly]

Thanks

Thanks for the info Robertob. I will send a note to Salty Monk.

I take it from your comment that I am jetted too lean with 107.5s.
I'll keep experimenting. I will take the bike for a quick run with the current set up before making a change though...just to be sure.

Thanks again.

PK

[nastyjones]

Nice to have a fellow gs'er in the neighbourhood. I'm in Tillsonburg. We drag raced a gs 1000 a few years ago with results that suprised a lot of the big boys. Keep at it, you'll find the right combo. Here is good advise....

http://www.factorypro.com/

Paul

[salty_monk]

With V&H 4:1 & Inbox K&N with stock airbox I ran 125's on a stock 1000. Stock on my bike is 115. I ran the needles one full notch down (maybe better with half).

I had ignition problems so I didn't get much time with it as I thought it was carbs & went from there to a DJ kit but when the ignition was working it ran good.

If you were closer I could have sent you some more jets to try but I think postage will negate any benefit.... I have a set of 122.5's as well but nothing smaller.

Listen to Chef... he knows more about the carbs than me. I can't remember what he posted but if it's a stock filter I would try maybe 5 over.

Kent has a stock 1100GL with V&H & inbox K&N, he runs 120 mains with a Dynojet needle. Stock on his bike is also 115 so it appears the extra bore really doesn't make a lot of difference to jet size.

Dan

[Paul Kelly]

man am I confused

Some of you good fellas have suggested going up in jet size with this big bore kit but I'm running waaay rich with the stock jets. Floats are in stock position at 23mm and needle is centred.

My local performance build shop said what I want to do is go smaller on the jets because of the bigger "signal" in the venturi due to the big bore. This seemed to make sense so I have been going leaner..hence my question..how lean to go. Note that they didn't tell me start from high rpm down...they want 600 bills to do this.

everything in the carbs but the jetting is in the stock position...so back to the drawing board.

I'm trying the 107.5s in a test run this evening so wish me luck.
Taking an extra set of plugs just in case. I'll let you guys know how it goes.

Thanks a mill

PK

[Paul Kelly]

Test ride done

Ok, that was a blast. During my 2hr test ride I've found out that with 107.5s I'm running lean at the top end. Had to pull a little choke and then she went like hell so probably a little lean.

It ran mediocre at mid throttle..kind of flat..and the exhaust note wasn't sharp sounding like it should be.

Next step is 110s for mains and another test ride...damn I hate that.