Junster
Member
Enflamed when you are at less then full throttle the slide is retricting the air. Try wide open with the choke at 1/3 or a little more. It kinda sounds like a air leak. Are you using a O-ring in the carb to intake connection?
Carby GT5 GEN 4 80cc: Rich or is this normal?
- Thread starter EnFlaMEd
- Start date
danlandberg
Active Member
Junster, I was thinking the same thing about Enflamed's problem. Intake leak. An intake leak can accrue in many places on these things, (under cylinder gasket, head gasket, case-half gasket, intake gasket. ect.)
danlandberg
Active Member
80cc slant head
I just installed a slant head I got from zoom. I also ordered a new head gasket with it. The new gasket was twice as thick as the one that came on the stock RAW kit.
It ran O.K. but not what I was expecting I then changed the head gasket back to the stock one. (I don't like to use used gaskets!) I now have good low, mid & top end power. But in top end (W.O.T) I get a harmonic sound (second vibration) Intermittently. When this accrues I have more power & speed but it's kind of a concern, (is it OK or is it going to blow) Any one have any ideas?
I just installed a slant head I got from zoom. I also ordered a new head gasket with it. The new gasket was twice as thick as the one that came on the stock RAW kit.
It ran O.K. but not what I was expecting I then changed the head gasket back to the stock one. (I don't like to use used gaskets!) I now have good low, mid & top end power. But in top end (W.O.T) I get a harmonic sound (second vibration) Intermittently. When this accrues I have more power & speed but it's kind of a concern, (is it OK or is it going to blow) Any one have any ideas?EnFlaMEd
Member
Junster: I am using an o-ring. I think the engine just needs to be run in. I might be asking a bit much of it at the moment. I think I have done about 190kms now and on a ride today I managed to get it up to 55kmh and it still felt like it wanted to go faster. It had a lot more rev range to play with still but it was getting a little intense for my liking. It seems to take on hills a fair bit better now but still if I give it too much throttle it bogs so I just go easy. If I ride at WOT with the choke at 1/3 the engine runs like **** and sounds like a machine gun. It also coats my spark plug in oil. I found this out by accident after I adjusted the needle clip and took it for a ride not realising I had left my choke partially on. You can imagine my suprise when it ran **** and I expected to pull out a white plug and it was completely covered in black goo. Took me a few minutes to figure out what had happened.
I have a boost bottle with a new intake manifold on the way so Ill double check for air leaks when I install that.
I have a boost bottle with a new intake manifold on the way so Ill double check for air leaks when I install that.
Junster
Member
Cool mine was the same way till the rings got seated in kinda had that booggg sound at WOT. Once your rings get seated in be sure to re-torque your head bolts. I was slowly loosing low end power and that was the fix.
EnFlaMEd
Member
Cheers for the advice Junster. I actually spent a while today trying to hunt down a torque wrench small enough for the job. I went to about 5 different places and noone stocks anything that small. I think Ill have to go to a tool specific place rather than an auto or hardware store.
Also for anyone interested. I received my boost bottle kit today and have just finished installing it. Something totally awesome that I have discovered is that the manifold supplied with the kit has made my carb sit much flatter! The angle difference comparing the stock manifold and the new one is barely noticeable but once installed it had made a huge difference. I can't wait to take it for a ride tomorrow afternoon! Its 11:30pm here at the moment otherwise Ide be on it now!
Also for anyone interested. I received my boost bottle kit today and have just finished installing it. Something totally awesome that I have discovered is that the manifold supplied with the kit has made my carb sit much flatter! The angle difference comparing the stock manifold and the new one is barely noticeable but once installed it had made a huge difference. I can't wait to take it for a ride tomorrow afternoon! Its 11:30pm here at the moment otherwise Ide be on it now!
Junster
Member
Harbor Freight has inch pound torque wrenches for $20 if you have one around. Glad it's coming together for you.
danlandberg
Active Member
EnFLaMEd: I used an inch pound torque wrench on mine, set it to 144 if your need 12 ft lbs.
EnFlaMEd
Member
Im in Australia Junster I should probably update my location!
Well bit of an interesting and frustrating afternoon. After work today I shopped around again for a torque wrench and eventually found a mirotorque (inch pounds) wrench that wasnt over $100aud. So I took it home and started tightening up the head bolts before I took it for a ride. For whatever reason the wrench didnt work at first and I sucessfully stripped one of the head nuts. I tested the wrench on a few other things and eventually it started working. Luckily I was able to get dropped off at the local hardware store and found some new nuts and then walked the 4km home. I quickly got my bike running again and took it for a ride.
This is what I have found since installing the boost bottle.
-it bogs a **** load then suddenly explodes with power when you twist the throttle
-it will continue to rev for a while despite the throttle being twisted closed.
-it doesnt seem to like holding idle after being given a big rev. It will do what I mentioned in the first line but then eventually it will either stall or rev its **** off. The idle speed changes regardless of the idle screw(the idle screw seems to work as usual when the engine is idling steadily). By that I mean the idle speed changes after each throttle application almost like the throttle is being stuck open sometimes but other times it stalls. It does not rev hunt or "surge". I tried checking for leaks but couldnt really find anything.
-the exhaust sounds great!
-once im moving and shifting through the gears it really does seem to run better. It seems to rev much nicer if its kept in the right range but otherwise it runs a bit rough. It seems to rev a lot quicker now too. Its especially noticeable at idle but I got from 0-40kmh in a time that would almost rival a car I think.
I should probably update my location!Well bit of an interesting and frustrating afternoon. After work today I shopped around again for a torque wrench and eventually found a mirotorque (inch pounds) wrench that wasnt over $100aud. So I took it home and started tightening up the head bolts before I took it for a ride. For whatever reason the wrench didnt work at first and I sucessfully stripped one of the head nuts. I tested the wrench on a few other things and eventually it started working. Luckily I was able to get dropped off at the local hardware store and found some new nuts and then walked the 4km home. I quickly got my bike running again and took it for a ride.
This is what I have found since installing the boost bottle.
-it bogs a **** load then suddenly explodes with power when you twist the throttle
-it will continue to rev for a while despite the throttle being twisted closed.
-it doesnt seem to like holding idle after being given a big rev. It will do what I mentioned in the first line but then eventually it will either stall or rev its **** off. The idle speed changes regardless of the idle screw(the idle screw seems to work as usual when the engine is idling steadily). By that I mean the idle speed changes after each throttle application almost like the throttle is being stuck open sometimes but other times it stalls. It does not rev hunt or "surge". I tried checking for leaks but couldnt really find anything.
-the exhaust sounds great!
-once im moving and shifting through the gears it really does seem to run better. It seems to rev much nicer if its kept in the right range but otherwise it runs a bit rough. It seems to rev a lot quicker now too. Its especially noticeable at idle but I got from 0-40kmh in a time that would almost rival a car I think.
Last edited:
