Carbon Monoxide Poisoning On Frame-Mounted Engines.


The GP460 OEM muffler's tailpipe is too short to bolt on exhaust hose/tubing.

I once used a side-piped Mitsubishi muffler on my GP460 engine. It had a longer tailpipe so I was able to connect an exhaust hose and SBP muffler. The Mits muffler was too restrictive at high rpms, even for the TLE43cc Mits engine.

I COULD drill mounting screws on the 460 muffler, then mount the Mits tailpipe and flange, then run the exhaust hose!:unsure:

However, I ordered the SBP expansion pipe, and it arrived last night. I'd rather use this pipe and hose, make more power and safely reroute the obnoxious fumes towards the rear axle.:unsure:
 
admit it... you just wanted a reason to get the SBP expansion kit right away... :)

Lol, Baron, as Tanaka 40 once mentioned to me, "until your next 'design change'..." lol

My friend Rick installed a Happy Time stock muffler on his 460 engine. It fit and it works. Sooo, if HT muffler fits, then SBP pipe SHOULD fit and work even better!:unsure:

AND IT DOES!

I installed it and a K&N air filter yesterday. Headpipe installed directly over my upside-down engine and below my 4-liter Happy Time fuel tank. Expansion chamber does a 90-degree at the seat tube, then extends via hose to SBP muffler near the rear axle.

Testrun up the grassy hill was my best ever, and in 2nd gear at that! Must be that extra midrange power.:geek:

Yesterday, I threw my bike into my van, dropped the van off at the repair shop, then rode my MB home, five miles away.

No dizziness, no headaches and quieter than the stock muffler.

Much more power, of course, looks good too. Pics to follow, when my friend Hawaii Ed and Rick see my bike.:giggle:
 
I installed it and a K&N air filter yesterday. Headpipe installed directly over my upside-down engine and below my 4-liter Happy Time fuel tank. Expansion chamber does a 90-degree at the seat tube, then extends via hose to SBP muffler near the rear axle.

ahhhh you have the engine upside down... that would explain the exhaust pointed right at your face... the possibility of CO poisoning is definitely higher than I would have guessed... or just dizzy from breathing the soot and smoke... either way-- yuck!

I got me one of those K&N type air filters right away as well. I have no idea how much it improved performance because I never ran mine with the weird stock one.

I'll probably get the SBP expansion kit, but not for a few paychecks... heck, maybe even not until tax time... I am still $1600 short of getting my car fixed... I would be closer if I hadn't bought the bike at all, but when I bought it I was still leaning towards selling the car... :-/
 
ahhhh you have the engine upside down... that would explain the exhaust pointed right at your face... the possibility of CO poisoning is definitely higher than I would have guessed... or just dizzy from breathing the soot and smoke... either way-- yuck!

I got me one of those K&N type air filters right away as well. I have no idea how much it improved performance because I never ran mine with the weird stock one.

I'll probably get the SBP expansion kit, but not for a few paychecks... heck, maybe even not until tax time... I am still $1600 short of getting my car fixed... I would be closer if I hadn't bought the bike at all, but when I bought it I was still leaning towards selling the car... :-/

Actually, the exhaust points forward in the 10 0'clock position.

We have three drivers. My bike replaces the third family car. I either get dropped off at work or bike in, 5 miles distance. Son goes to school 10 miles in the same direction. Van is in repair shop near my workplace, son drove the second car to work. When the van is ready for pick up, I ride my bike there, place it in the van and drive home. If our car goes in for repairs and the van's being used, I ride my bike to the shop, place it on the bike rack and drive home.

I save about $4,000 a year using my motorized bike, instead of buying another car.:geek:
 
easy cheap exhaust diversion

I was having similar troubles. So I took a 1/2 inch 90degree copper plumbing elbow and put it on the exhaust tip, angling it so the exhaust is pointed out the side of my bike. Then I used crimpers to tigten it in place. This works very well and it costs about a buck!!
 

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How is the motor mounted upside down?

Is it possible you got a headache from breathing gasoline fumes? (fuel from filling up the gas tank, or from spill/leak from bike?)

One time I got some fuel on me and rode anyway bc. I was already out there with my bike, and I got kind of sick. I wonder if it was from fumes or fuel getting in my skin. I felt nauseous and had a headache.

I used to commute a few miles a day, very early in the morning. Sometimes I would get headaches from the bright headlights, eyestrain from trying to focus so early in the morning after briskly waking and skipping breakfast.

I hope your bike runs great and you feel healthy. Good luck.
 
The GP460 I use looks similar to Tanaka engines. It has four motor mount bolts surrounding the 76mm clutch. Since it's a two-stroke, the motor can be mounted in four different positions. On this bike, the spark plug faces the ground.
No, it wasn't spilled fuel, but exhaust fumes. With the SBP exhaust, there are no more fumes to inhale. I feel healthy now. The 460 keeps breaking clutches, so I replaced it with a Tanaka 47R engine mounted upside down also.

Here's a picture:
http://motoredbikes.com/attachment.php?attachmentid=30075&d=1294959863
 
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Ref your post #9:
Hmmmm...Headache subsided as soon as you hopped in bed, huh? You don't think that maybe CO has anything to do with this, huh? Perhaps Mrs. 5-7Heaven might have a remedy or something to help with the headaches, ya think...???!!
 
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