Another new guy, just wanted ta say hey

[SKD]

just bought a 1981 gs1100 about 3 weeks ago and am workin on getting her better than new, shes stock now but came on here to get some ideas

[dragracer]

just bought a 1981 gs1100 about 3 weeks ago and am workin on getting her better than new, shes stock now but came on here to get some ideas

Nice original looking bike. Personally i would just restore it to show room condition and enjoy myself cruising around town.

On the flip side, the racer in me says extend/widen that swingarm, slip a Busa wheel on the back with a Shinko hookup, put an early model KAtana wheel on front, lower the front forks, bore the stock block as far as it will go and install some high compression pistons, get the head ported with a decent valves job, undercut the stock tranny and add an air shifter, add a set of 36mm flatside carbs, add a sidewinder and go play at the dragstrip.

[SKD]

i do need new exhaust, mines so rusted it looks like its gonna have a hole in it any minute, and i need some work on the airbox sooooo i was thinking, what would it take to install those sidewinder pipes and the k&n pod filters? i have the carbs in dip right now, well one of them anyway, lol, 1 gallon bucket berrymans carb dip. while i have the carbs apart should i order a jet kit and the exhaust? i fricken love that exhaust.

[moondogspot]

Side winder yes you will have to make a special pedal for the brakes.

A nice trick is to use a gsxr 1100 van&hines.

It tucks more under the bike than out to the side, sometimes it will clear the brake pedal.

You have to slot the flanges a little to the gs wider flang mounting pattern,but it will also give you alot more tire clearance ,if you wanna run the bike lower to the ground.

One other trick to a old school sidewinder on the street, go down to your local harley shop, or harley repair shop in your area.Ask them for a baffle for a dresser, rineheart or something for a hotrod harley, one they have pulled out to make the bike louder,they usually got a few layn around pay them for it even if they give it to you, next time they will really work with you thinking your not a mooooch.,

Cut it down make a back door to bolt it into the sidewinder.It wont make it quiet,just quieter. It gives a little back pressure, looks great on the dyno , cleans up the spikes of a sidewinder.

Carbs and emgo air filters.AKA cheap jet kit

Shim up the factory needles with some tiny washers, Radio Shack use to have these. Put three under the needle, or if it has the needle held in with a snap ring just flip over the plastic washer on top to the bottom.

Goto the tool store or go on ebay and buy a drill index ,remove the main jet. Open the main jet 2 sizes with a pin vice and drill bit.


Blast it up the road howz it feel. If it wont rev open up,open the main 2 more sizes.By the way if you over drill the stock jets dont sweat it, jets are cheap the whole jet kit is around 135.00 , jets are cheap like 4 bucks each or free from some shops and just drill them out to where it felt the best.

May need another washer.

If you cant tune it like this buy a jet kit, some work with this some dont, i have a dyno so i can jet it in with my own stuff.Ive had good luck with doing it this way.

moondogspot

[SKD]

wow, thats sounding like i need to just go with a jet kit...lol..im gonna look more into this, it sounds like i've got my work cut out for me. i think i may need to find a shop to fine tune it for me, theres no one around here thats even close to being an older bike tech, closest one is out in orange county and i've contacted him on another board. thanks for all your help.

[Big J]

congradulations and good luck on the new project. Be sure to post some pics as you go along

[SKD]

its almost embarrassing to post pics on here with all these dragbikes lookin all sexy, i really need to do some work.

[fj1289]

wow, thats sounding like i need to just go with a jet kit...lol..im gonna look more into this, it sounds like i've got my work cut out for me. i think i may need to find a shop to fine tune it for me, theres no one around here thats even close to being an older bike tech, closest one is out in orange county and i've contacted him on another board. thanks for all your help.

Fine tuning the jetting on a street bike is not difficult. It is just a matter of trial and error and keeping track of what you've done. Pick a baseline - like what moondogspot gave above, write it all down, ride it, and see how it acts.

To fine tune WOT, go up a size on the main jets, write it down, and ride it and see how it compares. If better, try bigger again, if not better, try smaller jets. Keep going until it runs the best at WOT.

Then, start with the mid range. See how it cruises and how it accelerates when you get into it. Then move the needles up (move the clip down if it is adjustable, add a washer under the clip if not adjustable). See how it does, and keep going until it is as good as it gets.

Adjust the idle so when the engine is warm and you blip the throttle the engine responds well and returns right back to idle. If it hangs up a bit, you need to make the idle richer. If it drops below idle and comes back up, you need to make the idle leaner. Sometimes you have to swap the low speed (pilot) air or fuel jets to get the idle right -- generally you know this because the idle screws end up too far in (nearly closed) or too far out (rady to fall out) before the idle gets right.

Most bikes in the 80's (stock) were lean down low (idle and needle adjustments) but fairly good to maybe a hair rich on top (main jets).

There's not really any magic - just trial and error. Of course, experience helps you do less trial and error to get there!

What you learn by jetting a set of carbs will always apply - even messing with FI. The engine doesn't care how it gets the fuel, adding or taking out fuel with brass or 1's and 0's is the same as far as the engine is concerned.

Good luck and enjoy learning - it's cool the first time you get the jetting "right" and feel how well the engine will really run.

That's a cool project - notheing to be embarrassed about!

[SKD]

Fine tuning the jetting on a street bike is not difficult. It is just a matter of trial and error and keeping track of what you've done. Pick a baseline - like what moondogspot gave above, write it all down, ride it, and see how it acts.

To fine tune WOT, go up a size on the main jets, write it down, and ride it and see how it compares. If better, try bigger again, if not better, try smaller jets. Keep going until it runs the best at WOT.

Then, start with the mid range. See how it cruises and how it accelerates when you get into it. Then move the needles up (move the clip down if it is adjustable, add a washer under the clip if not adjustable). See how it does, and keep going until it is as good as it gets.

Adjust the idle so when the engine is warm and you blip the throttle the engine responds well and returns right back to idle. If it hangs up a bit, you need to make the idle richer. If it drops below idle and comes back up, you need to make the idle leaner. Sometimes you have to swap the low speed (pilot) air or fuel jets to get the idle right -- generally you know this because the idle screws end up too far in (nearly closed) or too far out (rady to fall out) before the idle gets right.

Most bikes in the 80's (stock) were lean down low (idle and needle adjustments) but fairly good to maybe a hair rich on top (main jets).

There's not really any magic - just trial and error. Of course, experience helps you do less trial and error to get there!

What you learn by jetting a set of carbs will always apply - even messing with FI. The engine doesn't care how it gets the fuel, adding or taking out fuel with brass or 1's and 0's is the same as far as the engine is concerned.

Good luck and enjoy learning - it's cool the first time you get the jetting "right" and feel how well the engine will really run.

That's a cool project - notheing to be embarrassed about!

man, this site rocks, this is what i needed to know. im on it.need to get the carbs outta the dip first, then im on it..

[SKD]

ok, pods, vance and hines pipe and jet kit are ordered. lets see what she'll do after all that.

[SKD]

ok i have a question, with the exhaust and pods and the stage 1-3 jet kit, am i still gonna need to shim the needles? if so do i just get washers half as thick as the ones in there or thinner? ohhh man this is gonna fricken rockkk......

[dragracer]

The jet kit comes with adjustable needles anyway. Instructions should give a baseline. You will have to play with it to get the right performance. Be sure to buy a guage to synchronize the carbs so it will run right- it will be worth the $$ and time. I also bought an auxillary gas tank just for fine tuning the carbs to keep from yanking that freakin gas tank off over and over again.

Post pictures of your progress.

[D-Cu]

A nice trick is to use a gsxr 1100 van&hines.

It tucks more under the bike than out to the side, sometimes it will clear the brake pedal.

You have to slot the flanges a little to the gs wider flang mounting pattern,but it will also give you alot more tire clearance ,if you wanna run the bike lower to the ground.

moondogspot

Never heard of this before, unfortunately.
I have a V&H PCO pipe on my GS 1100 now, are the GSX-R pipes same diameter? Could I combine the nice PCO aluminum flanges and GSX-R sidewinder?

I've been trying to figure out the best way to lower the front end more without the front tyre hitting the exhaust and this sounds like a solution...

Thanks.

Juha

[D-Cu]

Actually I couldn't find a PCO pipe for the GSX-R so propably the answer to my previous question is no...

[SKD]

The jet kit comes with adjustable needles anyway. Instructions should give a baseline. You will have to play with it to get the right performance. Be sure to buy a guage to synchronize the carbs so it will run right- it will be worth the $$ and time. I also bought an auxillary gas tank just for fine tuning the carbs to keep from yanking that freakin gas tank off over and over again.

Post pictures of your progress.

picked up the carb sync tool last week, need to order an aux tank, im all over this....lol...thanks for the advise, im gonna need as much as possiable....