Author Topic: Engine not responding to throttle  (Read 965 times)

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mtrue77

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on: August 17, 2021, 09:26:00 pm
I had something strange happen today.  I 've been getting the motorcycle out on the road recently for some short rides.  10, 15, 20 miles.  Just trying to restore my confidence so I can take some much longer rides.  I've noticed sometimes a little jerkiness.  Usually when I'm rolling through the park at 25mph.   Actually, it's when I'm 20 to 30 and back and forth between 2nd and 3rd.  It's subtle, but I'm pretty sure it's happening. 

A little while ago, I was at an intersection.  Stopped.  1st gear, hand gripping the clutch lever.  Idling OK.  I twisted the throttle when the light changed, and got no response.  In fact, as I simultaneously began to release the clutch, the engine, of course, started to die.  Slowly twisted the throttle a couple of times.  No response.  Put it in neutral. 

I knew I had plenty of gas, but for lack of a better idea, I switched to RES.  I sat there for 20 seconds thinking, "Who am I going to call?"  This was in the park, and I wasn't holding anyone up.  Gave the throttle another gentle twist, and ... everything was fine.  So, off I went.  Speeds up to 50 (once outside the park).

Do you have any ideas?  I wouldn't guess that the jerkiness that I described is related to the engine not responding to the throttle (and then getting well on its own), but I don't know. 

Good thing I proofread this.  Auto-correct changed jerkiness to snarkiness.  Not an improvement in my book.
Michael T
Pittsburgh, PA
2009 AVL


AzCal Retred

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Reply #1 on: August 17, 2021, 10:13:43 pm
The tap has low flow & small diameter. I don't think it can flow enough to purge air thru the float bowl. My fuel line has some curl to it to accommodate an inline fuel filter,  and I've had to purge air in the line & filter a couple times. 5/16" works better than 1/4". Filling up the line & filter, then lifting it up to fill the float bowl, then making sure the line was filled solidly before reconnecting to the tap seems to work. Something to try.
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mtrue77

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Reply #2 on: August 17, 2021, 10:48:35 pm
Thank you.  1/4" to 5/16" gives you an increase in ID, but is it a tight enough fit?  Do you need a couple of tiny hoseclamps to prevent leakage around the petcock and carb nipples?   
Michael T
Pittsburgh, PA
2009 AVL


tooseevee

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Reply #3 on: August 18, 2021, 12:42:09 am
Thank you.  1/4" to 5/16" gives you an increase in ID, but is it a tight enough fit?  Do you need a couple of tiny hoseclamps to prevent leakage around the petcock and carb nipples?

     When I drilled out & rethreaded my tank to fit a new petcock (the petcock on a stock '08 AVL Classic is a HORrible piece of crap!) I replaced the tubing also with tube that was way too big for the barb fitting. It was a very loose fit. I just wrapped the barb in gasoline-proof Teflon tape until the tube was a nice tight push fit & put a tiny hose clamp on it (don't Krank on them). The TM 32 inlet is already larger. Larger than what?

       I know. I didn't make the petcock bigger, did I?, but it sounds good, doesn't it?  :)[/img] I don't rev it high enough to outsuck the petcock anyway  ;) ;) nudge, nudge.
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mtrue77

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Reply #4 on: August 18, 2021, 02:04:56 am
Thanks.  I've got a wood shop, not a machine shop.  I can make a box to put on the back, and I can even carve a wooden battery cover, but I'm not in the same league as you guys.  I don't see me drilling out the tank, and re-threading for a new petcock.
 That's why I still imagine building sheds for you next to mine.  "Build it, and they will come."

I'll keep doing these short rides for a few days to see what happens.  I hope nothing.  If I can get some consistency, I'm going to ride it into Ohio to visit the guys I bought it from.  Consulting and advice.  About 150 miles, round trip. 
Michael T
Pittsburgh, PA
2009 AVL