Author Topic: 1982 FT500 hesitates while going 20-40 MPH  (Read 854 times)

hednik4am

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1982 FT500 hesitates while going 20-40 MPH
« on: March 24, 2017, 09:10:11 AM »
Good morning fine folks. I just got my first bike and I just got her out of the shop. I didn't want a sportbike-mini or a cruiser. I saw this one a craigslist and liked a lot about it but it needed  quick tune up. I dropped it off and the shop cleaned the cabrs, gave her a tuneup, replaced the air filter (with a hiflofiltroair filter). So she stars up and idles great and runs great wide open but in 2nd gear and around 20-40 she just likes to jerk and hesitate a bit. Acts like its lean. Once above 45 and it goes away and purrs like a 3 week old kitten. Here is what we did and checked:
- Added a 2 MM washer to the jet needle
- Took the jets out and saw they were a 145 and a 52. Non stock main jet but a stock low speed jet. Wasn't sure if adding a 58 on the low speed would make a difference.
- Went through the carb with a find tooth comb and every hole was clear as could be.
- Checked compression and the valve clearance, making great compression as well.

Any ideas on what might be the issue ? Would a larger low speed jet improve this ? A oiled foam filter instead ? Thanks you all for the wealth of info already on here  :).

J6G1Z

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Re: 1982 FT500 hesitates while going 20-40 MPH
« Reply #1 on: March 24, 2017, 06:28:32 PM »
Congratulations on finding an Ascot.

If you haven't seen this yet, take a look: http://ascot500.com/index.php?topic=10.0

Change the low-speed jet to a #58.

You might consider changing the counter-shaft sprocket also.

Good luck
J.

hednik4am

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Re: 1982 FT500 hesitates while going 20-40 MPH
« Reply #2 on: March 24, 2017, 09:29:32 PM »
Thanks. That's something I have been reading up on a lot. I guess I might be a bit green so...The low speed jet being too lead would cause something like this. The SO took it out today and said it stopped but not seems to jerk a bit when in first and slowing down. These two things seem unrelated but it really like to idle or run wide open. Been reading about the sprockets. I have a moderate take apart and put back together skill so would this be something to try on my own?

triguyracer

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Re: 1982 FT500 hesitates while going 20-40 MPH
« Reply #3 on: March 25, 2017, 05:29:02 AM »
Hope  I can help with your  tuning problem,go to the 58 slow jet ,next 2mm is way to big of a shim for the needle this will cause a way rich condition,my self on my bike I had to make a shim out of a washer that was 20 thousands of a inch ,my main jet  right now is a 180 but I might go one bigger,the bike runs xclnt all thru the rpm range no flat spots  ,the only diff my bike has from yours is I have a White Brothers  pipe on it  with just three disks in it,have no airbox  and using a foam uni  filter.when you put a shim under the needle you need to make sure that the outside dia is not bigger than the clip or stopper on the top of the needle, if not the needle will not drop down to the bottom of the hole in the slide where you place it, the needle in causing  a rich condition , this sounds like your problem

hednik4am

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Re: 1982 FT500 hesitates while going 20-40 MPH
« Reply #4 on: March 29, 2017, 07:22:01 PM »
So it seems like the weird hesitation is linked to the brakes needing changed, forks need new springs too. Bike is running better but after 5 minutes running the exhaust is pretty hot and there i a clanging sound when I roll the throttle. Doesn't happen when idle really. Guy at the shop said it had good compression and valves seemed good. what might this clang be ? Would a recording help ?

triguyracer

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Re: 1982 FT500 hesitates while going 20-40 MPH
« Reply #5 on: March 30, 2017, 12:10:26 PM »
The rattling might be the inner pipe that's inside the head pipe that might have come loose 

hednik4am

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Re: 1982 FT500 hesitates while going 20-40 MPH
« Reply #6 on: March 30, 2017, 12:58:46 PM »
Would the part be on here ?


triguyracer

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Re: 1982 FT500 hesitates while going 20-40 MPH
« Reply #7 on: March 31, 2017, 09:06:25 AM »
Yes there is another peace of the front head pipe that is welded inside the head pipe that is not shown in the the parts picture, you have to remove the the head pipe and look in it to see if it is loose or shake the pipe and see if you can hear it rattle

hednik4am

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Re: 1982 FT500 hesitates while going 20-40 MPH
« Reply #8 on: April 01, 2017, 07:03:17 AM »
I got the header of and your assumption was correct. I banged on it a bit and could hear some rattling. Once it was completely off I could feel the inner pipe was loose. Now to the fix it part. Do I need to get this welded...Is that possible? Are there other options? I've search and not much anywhere about this. Even on other bikes. Thanks for your help on this triguyracer.

J6G1Z

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Re: 1982 FT500 hesitates while going 20-40 MPH
« Reply #9 on: April 01, 2017, 04:16:40 PM »
Just about every answer to your questions can be found in the top section of this board.

When the inner tubing comes loose, they can often be repaired by drilling holes along the backside of the outer tubing & then welding the two together through the holes.

J.