jonh Posted October 15, 2004 Report Share Posted October 15, 2004 Got my GG 200 Pro 02 last week and I am just starting to look and check the fueling. Cleaned the Plug off as it was black and wet ! I've run the bike for about a hour down the woods since, and the plug is now Black and wet again ! The bike doesnt pick up that well from low down especially when its warming up. I gave it a long hard and fast blast up a hill the other day and it smoked for a while then ran a lot better for a bit but it seems to be less responsive again now. I've read many posts about adjusting pilot, main jets and Air screws etc. but the problem is that I dont know which adjuster is which ? I'm used to Fuel injected VW cars so I dont really have much experience of Carbs at all. Got a Haynes Motorcycle Techbook from the library the other day so will be reading the Carb. section of that. But if anyone can give a basic explanation of how and where to adjust the carb ? Any suggestions on which plug is good for the GG 200 Pro ? Cheers Jon Quote Link to comment Share on other sites More sharing options...
alan bechard Posted October 15, 2004 Report Share Posted October 15, 2004 (edited) Carb tuning, noises, etc. are best done IMO with someone knowledgable there with you explaining what they are looking at / listening too. Before you start changing and adjusting anything, I suggest that you cover all the "basics" first. Proper fuel. Clean Fuel carb. Proper fuel oil ratio and proper oil. Clean, well oiled air filter with no residual in the airbox. New proper plug. Make certain of your base settings as R2w gave you while you are in there, and something I saw and noticed a couple of weeks ago, write your jet sizes on the bowl with a sharpie while you are in there. From the sounds of it, and the allusion that you made, your exhaust may be somewhat stuffed as well, and the black wet plug would also be an indication. I have not looked at a GG pro exhaust closely (Ron, Help) but will try and look this weekend. As to a very generic statement, most Trials center exhaust sections are not readily servicable. They tend to build up a fair amount of oil and spooge and are not IMO practical to clean for the average mechanic. It will be difficult at best to tune a bike with a poor performing exhaust system. If possible swap with someone for a day with a known good one and see what, if any difference it makes. The manual should show you what factors and rpm ranges the various jets, needle, screws and such effect. Oh,, And it may sound silly, and please do not take it insultingly,, but are you positive that you are turning on / off the choke correctly? and that the choke is moving full range? Edited October 15, 2004 by Alan Bechard Quote Link to comment Share on other sites More sharing options...
jtt Posted October 15, 2004 Report Share Posted October 15, 2004 Alan pretty much covered it....basics first. I usually like a slightly richer pilot setting than the spec R2 posted myself, but that's largely personal. Makes for easier starting up North here Also, don't get too caught up in looking at the spark plug. Contrary to popular belief, it's a very poor way to determine the running condition of the bike, as it's difficult to read correctly and there are far too many variables involved. Far better to go by feel. Closed to 1/8 throttle - air screw and pilot jet 1/8-1/4 throttle - air screw, pilot jet and throttle slide 1/4-1/2 throttle - slide and needle 1/2- full throttle - needle and main Quote Link to comment Share on other sites More sharing options...
jonh Posted October 15, 2004 Author Report Share Posted October 15, 2004 Thanks guys ! Gonna get all of the bits and pieces ready before I delve into the carb ! GG sent the wrong air filter for my model so thats gone back ! Gonna clean out the front pipe and re pack the rear box of the exhaust whilst I am waiting for filter and needles to arrive. ( Price up a centre box as well ! ) One other thing that I have noticed is that the rear box is split right where the cone meets the ring that seals to the centre box. So once I have emptied the box I will get it welded up ! This was obviously caused by the previous owner lifting the bike by the rear silencer ! The air filter is in poor condition ! I was gonna clean it out but I decided to leave it in place ( due to the absence of a new filter ) as I dont think it would be in one piece after cleaning ! Fuel is Shell Optimax with Castrol TTS F/S oil at 70:1 ( Too much oil ? ) Is Optimax OK ? I noticed on the TTS 2St oil bottle that it is for mixes down to 50:1 !? Should I use this oil ? If not which oil ? So.... for now all I will be doing is adusting the screws on the carb. ( Pointless cleaning all the Exhaust if I cant re jet the carb at the same time ) So.... as I undestand it the big screw is the Air Screw and the smaller screw is the Fuel Screw ? Also r2w you mention that the float bowl should be parallel ? I take it that this means that the whole carb should sit level with both wheels on the ground? Sorry if the questions are a bit nieve but I gotta start somewhere ! I dont want to be like a some people who buy bikes and ride them without setting them up properly and then complain that they cant finish a trial cos its let them down ! Thanks Again JonH Quote Link to comment Share on other sites More sharing options...
jtt Posted October 15, 2004 Report Share Posted October 15, 2004 (edited) Jon, the small screw towards the cylinder is the fuel screw. Clockwise makes the mixture leaner (less fuel), counterclockwise makes it richer (more fuel). This carb does not have an air screw, but rather the fuel screw, which effects the same range only in reverse (out on an air screw makes it leaner). The large screw you see, more to the center of the carb is the idle screw. This is only a stopper to hold the slide up to achieve proper idle speed. I'd go ahead and clean the exhaust anyways. Chances are that is where your issues are. Unless the previous owner messed with the jetting it should be close in that department, however may be dirty. You rarely need to replace jets, unless trying to change the mixture. A careful cleaning and blowing out with compressed air can do wonders. Your fuel and oil should be fine, as long as it's fresh. 70:1 should work fine. Not much need to go richer on these modern bikes in most cases. The "float" that R2 is referring to is the internal float height. When you remove the carb and float bowl, you will see how the fuel is metered into the bowl by these floats acting on a small needle valve. As the fuel is used up from the bowl, the floats drop with the level. As they drop the needle valve is opened and the bowl replenished, until the floats come up high enough to shut off the supply again. The height measurement r2 is referring to is the height where the needle valve closes off. You will see it as you lift and lower the floats in your hand. The height is varied by very gently bending the tab where the needle attached to the floats. Set this height so that the floats are level when the needle just closes. I think, if memory serves me, the measurement from the bottom of the carb casting (surface that mates with the bowl itself) is 16.5mm when set correctly, and the needle just closing. I hope that makes sense. HERE is some good reading that may help you make sense of all this. Edited October 15, 2004 by JTT Quote Link to comment Share on other sites More sharing options...
jonh Posted October 15, 2004 Author Report Share Posted October 15, 2004 Got it now !! Youve turned the lights on !! I will repack the Exhaust and clean out the front pipe and carb. Not sure if I can see a fuel filter on the bike at all ? Had a little square one on the 96 Fantis Section that I used to own. Do I need one ? Any ideas for Plug spec for the 200 Pro ? Jon Quote Link to comment Share on other sites More sharing options...
jtt Posted October 15, 2004 Report Share Posted October 15, 2004 A simple inline filter is never a bad idea. As far as plug goes, NGK BPR5ES is the standard plug and works fine. 0.5-0.6mm gap Quote Link to comment Share on other sites More sharing options...
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