Boss is what about a third of an inch in diameter?

Dennis i wondered why i couldnt do plug reading anymore! I know how to do the proper plug chop but still cant tell a damn what color they are.I suspected it was because modern engines run much cleaner?Now i know!

I did some minor plug reading decades ago but to be honest i usually just listened to the engine.I had nothing but two strokes back then- it's easy to hear when they are rich or lean.
Not so with these 4 strokes :-(. When i bought my GS it was running bad at full throttle under load.I did the little cheat with the choke but still couldnt tell if that made it worse or not.
All i could do was trial and error.  For the record it was rich.Fixed now

Skipping the intro I originally planned for this reply that has nothing to do with original post... (make a long story short)
I think the GS gets "poor" gas mileage by modern standards on purpose. It's one of the very few air cooled bikes I could even find for sale at my local dealer. I now believe the mixture is set the way it is with the factory intake and factory exhausts to run at a mixture that doesn't overheat the head.
I may be off here, but my buddy who has an airplane explained that more gas actually reduces the temperature of the exhaust manifold? If that is correct, it could explain why the GS mileage is less than stellar and the carbs can be 'tuned' for better performance so easily. I THINK they come factory running rich.
Anyone else had any observations along these lines?

The theory is correct,i richer mixture runs cooler. However i think the GS500 is usually setup a bit lean.

My theory on fuel economy is that it's not as good as it could be because its the kind of bike that encourages full throttle so often

Quote from: Zithromax on December 27, 2014, 01:32:03 AM
Skipping the intro I originally planned for this reply that has nothing to do with original post... (make a long story short)
I think the GS gets "poor" gas mileage by modern standards on purpose. It's one of the very few air cooled bikes I could even find for sale at my local dealer. I now believe the mixture is set the way it is with the factory intake and factory exhausts to run at a mixture that doesn't overheat the head.
I may be off here, but my buddy who has an airplane explained that more gas actually reduces the temperature of the exhaust manifold? If that is correct, it could explain why the GS mileage is less than stellar and the carbs can be 'tuned' for better performance so easily. I THINK they come factory running rich.
Anyone else had any observations along these lines?

Every carburated bike sold in the US market since the 70's (maybe longer) for street use have had to comply with emission standards. The GS is no exception, on an otherwise bone stock bike I went up one size on the pilot and the mains, after that the throttle response was vastly improved. To get into the states you could pretty much bet that Suzuki took an Ok running engine and then dropped the jet sizes one number to help the bike meet EPA Emission standards. Even with the plus one jetting I could get mid 60's for mileage consistently on the open road, I don't think the GS gets that bad of mileage at all. 

sorry about the plug chop argument.... my last plug chop was using 120 race gas in a 2T GP bike.  so not valid unless way the heck lean or rich

Thought you were going out in the canoe today instead of staying in and arguing about feckin carbs!! 

Quote from: Suzuki Stevo on December 27, 2014, 07:18:07 AM
Every carburated bike sold in the US market since the 70's (maybe longer) for street use have had to comply with emission standards. The GS is no exception, on an otherwise bone stock bike I went up one size on the pilot and the mains, after that the throttle response was vastly improved. To get into the states you could pretty much bet that Suzuki took an Ok running engine and then dropped the jet sizes one number to help the bike meet EPA Emission standards. Even with the plus one jetting I could get mid 60's for mileage consistently on the open road, I don't think the GS gets that bad of mileage at all.

Have to agree 

This includes pretty much anything with a carb. My ATV's all ran like crap until I put bigger jets in them.

Quote from: Ron888 on December 26, 2014, 09:35:59 PM
Dennis i wondered why i couldnt do plug reading anymore! I know how to do the proper plug chop but still cant tell a damn what color they are.I suspected it was because modern engines run much cleaner?Now i know!

You can still do a plug chop but reading it is different than the old school "tan".

It's also best to cut the plugs open so you can see the very top of the inside of the insulator. Most people don't want to waste a good set of plugs.

http://www.rays-shop.com/2010/01/how-to-read-your-spark-plugs-they-are-telling-you-whats-going-on-in-there/

Measuring with an O2 sensor and getting decent readings, then pulling the plugs and looking at them and they are essentially white, tells you that the old plug chop method may not work. I actually figured this out after working on a carb swap a few years ago and I couldn't get the right jetting and performance. That's when I bought the first O2 sensor and it helped solve the problem. Put the sensor bung right in the exhaust pipe and the gauge on the dash. Pretty cool to see the Fuel/Air mix real time and it answered the question of what was wrong.

Quote from: dennisgb on December 27, 2014, 09:57:06 AMPut the sensor bung right in the exhaust pipe and the gauge on the dash. Pretty cool to see the Fuel/Air mix real time and it answered the question of what was wrong.

If all my bikes where not EFI already...the above statement would have given me a woody so big you could hang a towel on it! 

Quote from: Suzuki Stevo on December 27, 2014, 10:16:04 AM

Quote from: dennisgb on December 27, 2014, 09:57:06 AMPut the sensor bung right in the exhaust pipe and the gauge on the dash. Pretty cool to see the Fuel/Air mix real time and it answered the question of what was wrong.

If all my bikes where not EFI already...the above statement would have given me a woody so big you could hang a towel on it! 

Now that was funny Stevo 

Now to get really technical because I know you guys love that.

Stevo, your EFI bikes have a bung in the exhaust...a wideband O2 sensor is critical for the real time mapping on EFI. 

I'm actually working on converting an old CBR engine to EFI...and the bung in the exhaust is a critical factor...and locating it correctly. I have a few holes in the pipe I had to plug. 

It's on the bench and tied to my laptop...with the mapping software. I still don't have it right...but close. It's actually just a side project to see if I can do it.

That sounds like an awesome project. I'd like to see a pic of EFI on motorcycle. Does it have a single throttle body and intake manifold, or is it multiport? I looked into buying a kit to put EFI on my 62 VW dunebuggy (also because it's air cooled) and the picture in the kit looked really "involved" if you know what I mean.

Quote from: Zithromax on December 27, 2014, 04:04:27 PM
That sounds like an awesome project. I'd like to see a pic of EFI on motorcycle. Does it have a single throttle body and intake manifold, or is it multiport? I looked into buying a kit to put EFI on my 62 VW dunebuggy (also because it's air cooled) and the picture in the kit looked really "involved" if you know what I mean.

It's a little bit crazy if you want to know the truth...that's why it's a bench project. The engine is a 1988 CBR600. The throttle bodies are from a CBR600F4i along with some sensors and wiring. I'm using a universal fuel injection control module. There are a ton of things that had to be fabricated and sourced to get it to work. High pressure fuel pump, manifold adaptors, sensors...hall effect for ignition...the list goes on. It still doesn't run good enough to put it in a bike. It looks kind of cool tho

Sledge, i went for a ww kayak run on dec 25 and a lake run on the 27th.... i can discuss technical majic at night while watching Project Binky....... droooool..... y'all brit's are friggin MAD...

Watched this last night.........  http://www.bbc.co.uk/programmes/b04wwfwk....you need to look out for it on your side 

Was going to send out for a curry but I couldn't find the feckin menu!!!

just get a vindaloo and a warm lagar.......

So, i wound up making the screw modifications anyway. Just as a start i wanna say this:

My setup roughly: open podfilters and an takkoni slip on.
Pilot screw setup: 3 full turns out.

Against my own expectation, my first try was just 3 turns out, and it drives very nice now (better then before).

But i guess, if you want to be able to easily adjust the screws, here's what i did

Step 1. Obtain your pilot screws.



Step 2. know someone with a lathe, and you're going to drill with 4 kinds of drills

1. A centerpointer.
2. A 1.5 mm drillbit
3. A 1.98 drillbit
4. A 1.98 spacer (i guess that's the translation of it. the bit under the package on the photo under here.)

Go no further then 5mm into the screw!!



Here are some photos of the progress.





5. Press a 2.0 mm steel thread trough it. i did this with the drillbit on the lathe bench. 5cm was my perfect length, it would bottom out on the drillbit, ensuring a good press.



6. This is what you end up with. Simply bend the ends in a 90 degree angle.



7. My complete kit.



8. This is the final result. very handy if you feel you need to tune your screws.



I wish you all a happy 2015!!

Too long. If you ever forget and stick you hand in that gap, you will break something.
They shouldn't be longer than the bottom of the float bowl.
Cool.
Buddha.

So, not to long if i dont forget when i put my hand in there. Thats what i was going for.