TNG Venice power mystery
 

My 2006 TNG Venice starts fine runs up to 10 mph or so then loses power. We have tried and checked everything short of the muffler clog. Looking at that tomorrow. All lines operative. Compression 150. Pure gas. new Mikuni carb. new petcock. all spartkplugs are fouled, oily and black-gone through four. Help!:hmm:

Have you checked the valves?

Hi
Welcome aboard
Pleased to meet you
Black oily fouled plugs are indications of bad oil seals and or piston rings
Your gonna have to open up the engine and see whats going on to find out for sure im sorry to say
You have my best wishes that its an easy repair
Take care and ride safely
Yours Hank

fouled plugs with what seems to be oil is normally a rich mixture. it looks like oil from carbon build up. loss of power like that could mean your exaust valve is not seating properly, when you checked compression was the motor cold or did you check it at operating temp? it makes a difference.

when you have bad rings or bad valve seals you normally see blue smoke coming from the exauhst

also clogged exauhst will cause the pipes to glow or radiate heat to the point you notice. this is caused to the amount of friction of the air passing threw. its hard to tell your the exact problem without the bike in front of us. so my advice, go as deep as you possibly can in the diagnosis before you tear anything apart. not saying im right or anyone else is wrong because that would be silly. but I know from a mechanical background that details in the diagnosis will tell you the exact problem every time with a small engine.

If you have a 2006 TNG Venice..it should be a 2 stroke engine. Do you premix or use the oil pump? It sounds way too rich..so either the main jet is too large..or if premixing you are mixing too much oil. Most premix at 32:1..which is 4 oz oil to a gallon of gas. I would also check for a weak spark as this will not allow proper combustion and foul plugs quickly. I just had that with a customers Scoot. It would spark but the spark was yellow/orange vice blue. It just kept fouling plugs left and right and had no power. Another thing is..if you used to have a Leader...TK or QJ carb then replaced it with the Mikuni...although the same size carb..the Mikuni prefers different jet sizes than the 'clone' carbs do..so chances are you may be running way rich.. What size jet are you using..and is this a big bore engine or stock 50cc?.. Let us know and we can go from there..:tup:

Hi
His scoot is a 2t so no valves as they use reeds
And it would normally blow some blu smoke 2ts are notorious for that
Taake xcare and ride safely
Yours Hank