81 GS650 tuning help Dynojet stage 3

[Gsnoob]

Hey guys I have a Dynojet stage 3 kit on way for my 81 gs 650 just wondering if anyone has any recommendations to help my install and tuning go smooth as possible. Like where to start out on my air/fuel and how to use the clips that come in the kit things like that. Thanks

 

[Guest]

what do you have done to your gs650 to warrant a stage 3 kit?

Not trying to come off as rude, just curious...

 

[Bribird]

well, when I did mine...I chased my tail endlessly...would not recommend it.....although it is easier to get the carbs off when running pod filters. That kit comes with 2 jet sizes...I would use the smaller of the 2 sets and start out on the 2nd to lowest setting on the needle as far as the clip goes.

 

[Gsnoob]

Bought a bike with chopped off open pipes and its never been rejetted guys chopped it and parked it cause he said it was to loud so im putting in the stage 3 and going to add some pods and next spring im doing a V&H 4-1, starting with the jets so i can atleats ride it witout buring my pistons or valves.

what do you have done to your gs650 to warrant a stage 3 kit?

Not trying to come off as rude, just curious...

 

[Gsnoob]

Okay so kit is here and just my Luck no install guide so i call dynojet "Oh I'm sorry it apears that modle kit doesnt come with a detailed install guide" Awesome lol guess they assume if your installing it in this old bike you prolly know what your doing lmfao, So couple questions kit comes with 155 and 160 main jets wich should i use and where are the mixture screw caps kit came with a drill bit and screw to remove caps however not sure where they are located, install looks pretty simple although im not entirly sure what to do with the glue and air corrector guy on phone told me glue was to install air corrector so any pointers would help. Now if i can get all the carb screws to come out without stripping will be all good. Can i replace the stupid phillips head screws on my float bowls with like an allen headed screw or is that not recommended. Well alot in this post so ill let the pros get to it thanks

 

[Bribird]

Okay so kit is here and just my Luck no install guide so i call dynojet "Oh I'm sorry it apears that modle kit doesnt come with a detailed install guide" Awesome lol guess they assume if your installing it in this old bike you prolly know what your doing lmfao, So couple questions kit comes with 155 and 160 main jets wich should i use and where are the mixture screw caps kit came with a drill bit and screw to remove caps however not sure where they are located, install looks pretty simple although im not entirly sure what to do with the glue and air corrector guy on phone told me glue was to install air corrector so any pointers would help. Now if i can get all the carb screws to come out without stripping will be all good. Can i replace the stupid phillips head screws on my float bowls with like an allen headed screw or is that not recommended. Well alot in this post so ill let the pros get to it thanks

OK...I would start off with the 155 Dynojet jets. I would also replace the phillips head bolts with stainless allen head bolts. The air correctors go into the little holes on the intake side of the carb throat..I think they are on the right side of the throttle bore...just a little dab of glue and then use the driver tool(little metal pipe thingy with a shoulder on the end) to seat the correctors flush. Removeing the mixture caps is pretty easy, just be careful you only drill just thru the cap...I have seen many a man damage the mixture screw head itself and then you will have a hard time adjusting it. The mixture screws are dead middle topside of the engine side of the carbs. Looking at my carbs it would be just to the left of the red choke levers close to the top caps of the carbs.


hope this helps. good luck

 

[koolaid_kid]

I would snag another instruction pdf off their site. They are very similar; this one is from a GS1100G: http://www.dynojet.com/pdf/3103.pdf

 

[Bribird]

I would snag another instruction pdf off their site. They are very similar; this one is from a GS1100G: http://www.dynojet.com/pdf/3103.pdf

ya..very true. The one for and 850 is pretty much dead on also.

gots to remember..the 650 is the red headed stepchild of the GS world...lol

 

[trippivot]

easy as pie

easy as pie

if you have ANY doubts at all PAY SOMEONE who knows


Basic Starting Point
155 mains
2 turns out on the mixture screws

middle notch on the needle- no washers

fresh gas and new NGK spark plugs

sync and lean idle drop all 4 cylinders when you warm it up.

get the best smoothest idle before you try to ride it

get back to us where the stumble is. Tuning it out takes a scientific method and accurate information gathering

 

[Gsnoob]

Just curious you mention no washer on the new needle? The install sheets all say use the washer not doubting you just wondering what difference leaving it out makes I got everything installed lastngiht but got stuck on the awesome little c-clips holding the old needles in didint have a clip puller so borrowing one form shop today hope to finish tonight. Also sheets say remove float bowl tube if there is one what tube are they refering to? And yes i have doubts but I wanna learn myself how to tune this bike and cant find anyone local who will touch the bike so all on me also there is just something about saying yeah i did the work my self that makes you feel proud to be riding it. Unless of course i fck it up completly and then will be no riding but lets hope that doesnt happen lol

if you have ANY doubts at all PAY SOMEONE who knows


Basic Starting Point
155 mains
2 turns out on the mixture screws

middle notch on the needle- no washers

fresh gas and new NGK spark plugs

sync and lean idle drop all 4 cylinders when you warm it up.

get the best smoothest idle before you try to ride it

get back to us where the stumble is. Tuning it out takes a scientific method and accurate information gathering

 

[Gsnoob]

lol thanks for the links to the install guides so I must ask just cause i am as the name says a noob to the gs why is it the redheaded step child of the GS world lol.

ya..very true. The one for and 850 is pretty much dead on also.

gots to remember..the 650 is the red headed stepchild of the GS world...lol

 

[koolaid_kid]

Most chain people went with either 550 or a 750 and most shafties went with the 850. Personally, I prefer the 650E for almost everything except the open road due to the difference in weight. Even the 650G is lighter. 50 pounds may not sound like a lot until you have been pushing it around all day.

 

[Gsnoob]

K so update on the situation started with the 155s and clips on middle notch, couldnt get it to idle and didnt wanna run even with me throttling it tried adjusting mix couldnt get it, pulled it all back out put the 160s in with clip on 3rd notch down, finally she idles had to udjust the idle screw just a tad but it wouldnt idle right away, after the idle screw adjust she idles flawless, its late so will do some chops tomorrow, I could seem to accel rpms through low and mid smooth she had a bit of backfireing in the higher range any suggestions on how to correct that or why its doing it? Everything seems to be really close to good except that bit of backfire. Of course i wont know for sure till i do my chops but things are looking good so far.

 

[koolaid_kid]

Have you synched the carbs yet? This must be done as soon as you get it running. BTW, the mains have absolutely nothing to do with idling. They only come into play after 1/2 throttle. I suggest the backfiring is either the points or an intake leak. Have you checked the the timing using a timing light yet? Or the static timing if that is the procedure for your bike?

 

[Gsnoob]

Then im assuming it musta been changing the needle clips that allowed it to run, when you refer to the points what points do you refer to it most likely is intake leak if that can cause the back firing I didnt fully tighten things just wanted to see if it would start and idle, tonight after work ill go through and tighten the intake boots and everything else down, this will be my first time syncing carbs talos do i need a carb sync tool or can it be done without? Have not checked timing yet can jetting a carb throw the timming off cause im fairly sure timing was okay but i will check it, and thanks for the help as ive said alot of this is also a learning experience for me.

Have you synched the carbs yet? This must be done as soon as you get it running. BTW, the mains have absolutely nothing to do with idling. They only come into play after 1/2 throttle. I suggest the backfiring is either the points or an intake leak. Have you checked the the timing using a timing light yet? Or the static timing if that is the procedure for your bike?

 

[Gsnoob]

Alright soooo its looking like a sync tool is a must and just going off some plug chops isnt gonna cut it damn, I was so hoping to get my bike out on the road tomorrow I dont have a nanometer, and none of the local shops have one. lol and to top it all NONE of the local parts stores or hardware stores have one to sell me "sigh" Im guessing noone has any suggestions to get them synced and running good without the tool either Im just not seeing a way around it.

 

[Bribird]

Alright soooo its looking like a sync tool is a must and just going off some plug chops isnt gonna cut it damn, I was so hoping to get my bike out on the road tomorrow I dont have a nanometer, and none of the local shops have one. lol and to top it all NONE of the local parts stores or hardware stores have one to sell me "sigh" Im guessing noone has any suggestions to get them synced and running good without the tool either Im just not seeing a way around it.

I have a Morgan Carbtune II..it works great. I have used the other types and like the Morgan one the best.

 

[Gsnoob]

What's a good idle rpm for this bike. I think I mentioned before its a 81 gs650

 

[Gsnoob]

Okay i pulled carbs back out bench synced them have sync tool commign tomorrow, I Worked it out so it idles very smooth. Against my better judgment i just had to take it around the block and see what rpm range felt like not even 5min running WOW its like a competly different bike however I just had to hit it a little and see and as i thought it stumbles and falls flat on its face if I lay on the throttle goes like never before up to about 5-6k range thats when she hesitates and feels like has no power, only hit it once afraid id hurt something not having it synced yet. got back and still idleing smooth any suggestions about the high rpm range?

 

[Bribird]

ya..that is where I was too. the hard part is knowing whether its lean or rich. being that mine wasnt smoking..I assujmed lean and raised the needle a notch...also need to know if you have enough flow resistance to draw the needle up and let the jet flow. With the stock airbox and stock carb setup, all these things were worked out by Suzuki engineers. If I had it to do over again, I would have stayed stock and maybe just played with the main jet a bit or maybe shimmed the needle.

good luck with it.