|
|
Post by Jwhood on Oct 21, 2014 23:45:59 GMT -5
just a small leak on a Tgb or basically any 2t motor will act crazy I'm 99% sure its an air leak or reeds are shot,if you lived in Maryland I'd have you up in running in no time,not to long ago I fixed a local guys Tgb and it runs great now!!!!
|
|
|
|
Post by Elektrey on Oct 22, 2014 8:29:17 GMT -5
just a small leak on a Tgb or basically any 2t motor will act crazy I'm 99% sure its an air leak or reeds are shot,if you lived in Maryland I'd have you up in running in no time,not to long ago I fixed a local guys Tgb and it runs great now!!!! yeah i'll check reeds/leak after I try this new oil. oh btw you said the reeds are on the bottom or something? www.cobrasales.com/parts/tgb/TGB%20R50X%20Parts%20Manual.htmon diagram 2 it shows it on the top of the engine? |
|
|
|
Post by Jwhood on Oct 22, 2014 12:11:54 GMT -5
the reeds are on the bottom of the intake manifold,the manifold is the silver tube that your carb hooks up too,your carb hooks too a black tube and the black tube hooks on too the manifold
|
|
|
|
Post by Elektrey on Oct 22, 2014 16:58:51 GMT -5
the reeds are on the bottom of the intake manifold,the manifold is the silver tube that your carb hooks up too,your carb hooks too a black tube and the black tube hooks on too the manifold How hard is the intake manifold to take off? I see 3 hard-to-reach bolts and one strange looking round head bolt or something. It looks like it might require the motor to be seperated because the bar for the mount might be in the way? |
|
|
|
Post by Jwhood on Oct 22, 2014 17:11:29 GMT -5
You need to take the two circlips off inside the motor mount once you get that done you need to take the steel rod and slide it out then you will be able to access the manifold bolts it uses a standard allen head wrench to get the three bolt out and then a pair of vice grips to get the odd bolt out be careful pulling the manifold out because the gasket will rip in half get some Permatex sealant copper kind will work great i also bought new gasket material and made a new gasket I put the cooper sealant on top and bottom of new gasket for a good seal also get a new allen head bolt to replace the odd looking bolt this area on a 2 stroke scooter is a bad place for leaks
|
|
|
|
Post by Elektrey on Oct 22, 2014 19:09:21 GMT -5
You need to take the two circlips off inside the motor mount once you get that done you need to take the steel rod and slide it out then you will be able to access the manifold bolts it uses a standard allen head wrench to get the three bolt out and then a pair of vice grips to get the odd bolt out be careful pulling the manifold out because the gasket will rip in half get some Permatex sealant copper kind will work great i also bought new gasket material and made a new gasket I put the cooper sealant on top and bottom of new gasket for a good seal also get a new allen head bolt to replace the odd looking bolt this area on a 2 stroke scooter is a bad place for leaks good info. Looks like I'll try it with the new gas before I go looking at the valves. |
|
|
|
Post by Elektrey on Oct 23, 2014 18:30:57 GMT -5
Tried with the new oil.
It acted a lot better at 32:1 than the AMSoil did at 80:1 but still was acting 'rich' at idle. Weak idle, would die sometimes, hard to start warm, when you went WOT it would bog for a second and then launch.
Could these be symtpoms of a lean idle? or would only a rich act like that?
What are symtpoms of bad valves?
Oh and I like the new oil it's actually smokeless unlike the saber which smokes. Also near odorless.
Was thinking of just opening up the airbox more and more untill either the idle fixes itself or it starts bogging in the rest of the range due to lean.
If the idle never changes at all I can rule out afr.
|
|
|
|
Post by jareeb on Oct 23, 2014 22:36:55 GMT -5
did you check for leaks yet?
|
|
|
|
Post by Elektrey on Oct 23, 2014 23:07:31 GMT -5
did you check for leaks yet? No but I had forgotten about that. Will brake parts cleaner work? Also the spark plug looks quite normal. The other ones were covered in oil when I took them out when I was using amsoil.   |
|
|
|
Post by jareeb on Oct 23, 2014 23:41:56 GMT -5
it will work. before you do anything else get the engine at running temp and start spraying! plugs dont have much burn on them yet
|
|
|
|
Post by Elektrey on Oct 25, 2014 12:40:39 GMT -5
Ok so I was going to check for leaks, but: 1) couldn't find the tube for the sprayer so it was just liquid coming out of the can. 2) couldn't get it warmed up and idling. What happened was this: 1) started bike, idled at 2k RPM, then slowly declined over about a minute before dying because of too low RPM. So I took out the spark plug and checked it:   So then I changed the air mixture screw all over from turned all the way in to all the way out. Would not start either way.(cranked and sort of fired a few times at 1000RPM but died after the starter stopped or very shortly after). Then I covered the air filter with a rag and tried. Same thing. Then I started to remove the pieces of tape on the air filter one by one and trying. Still would not start. When I had no more tape on the air filter I gave it throttle to start it and noticed it was VERY responsive and didn't slowly creep up to takeoff. This gave me an idea. I took off for a ride on it and noticed it actually did NOT bog down.(remember my previous ideal tune was with about 60% of the air filter covered by tape). I also noticed that the idle was flawlessly smooth with perfect throttle response. When I stopped the idle took a while to come down but when it did, It did not die. So far I've pulled the plug after I came to a stop in my garage, and I think it looks lean, what do you think?   I have not started it yet but I'd be willing to bet it won't die after a while and fixed the idle problem. Now I just have to worry about it being too lean. Is it strange that a simple oil change caused this much of an afr difference? maybe due to an extreme viscosity change or something like that. I don't know what the previous oil was so it could have been the completely wrong oil for all I know. |
|
|
|
Post by 90GTVert on Oct 25, 2014 15:58:40 GMT -5
That is lean. You can look at the mix ring as shown in the tech library if the plug is fresh, but now you're not putting any color on the porcelain or on the base. The hanging RPM is also telling you it's lean. When there's an adequate fuel supply it will return to standard idle speed. You really should install a larger main jet, or really get a selection and tune for best WOT, then work on the rest of the settings (needle & mix/pilot).
|
|
|
|
Post by Elektrey on Oct 25, 2014 16:24:03 GMT -5
That is lean. You can look at the mix ring as shown in the tech library if the plug is fresh, but now you're not putting any color on the porcelain or on the base. The hanging RPM is also telling you it's lean. When there's an adequate fuel supply it will return to standard idle speed. You really should install a larger main jet, or really get a selection and tune for best WOT, then work on the rest of the settings (needle & mix/pilot). If I pulled it out after It was stopped in my driveway and idled for about 30 seconds, is it showing the AFR of the idle or is the ride I did also being shown somehow? |
|
|
|
Post by niz76 on Oct 25, 2014 16:56:57 GMT -5
Proper plug "chop" is to test only one fuel setting at a time; if checking WOT you'd immediately kill the engine after WOT to get an accurate reading... same for other carb settings... The pics that you're posting don't actually show what you should be looking at- the mixture ring down inside the plug... Check in the info in the tech section...
|
|
|
|
Post by 90GTVert on Oct 25, 2014 20:11:24 GMT -5
You wanna look deep down in the plug or literally chop it (cut off the threads) if you're gonna read WOT mixture. Still run it WOT and try to shut it down. It gets expensive cutting up plugs. You could buy a jet kit for the cost of the plugs you can go through if you do lots of chops. I generally use other method and use chops as a last resort or a final check if the tune worries me. 49ccscoot.proboards.com/thread/1727/spark-plug-reading-tuning-info |
|
