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I inherited my fathers 80 sportster that was sitting in his barn for nearly 20 years. He left gas in the tank “what a mess”. After recoating the tanks, changing all new lines and much more work, I finally brought her back to life. The problem I have now is that it’s slipping pretty bad in first gear. Should I get it rebuilt, flush and change the fluids ? Any thoughts?
Thanks in advance
 

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If the clutch slips in first, it should slip worse in higher gears. Pull the primary cover, disassemble, clean, and inspect the clutch assembly. Replace any worn parts and reassemble.
 

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I inherited my fathers 80 sportster that was sitting in his barn for nearly 20 years. He left gas in the tank “what a mess”. After recoating the tanks, changing all new lines and much more work, I finally brought her back to life. The problem I have now is that it’s slipping pretty bad in first gear. Should I get it rebuilt, flush and change the fluids ? Any thoughts?
Thanks in advance
Try adjusting the clutch first before taking it all apart. Follow the service manual or look up how to do it on YouTube.
 

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That clutch has three adjustments. The release is adjusted with a set screw under the adjuster plug. Then there is an adjustment on the cable. And just to make it really suck, there are select fit spacers on the pressure plate studs. If its slipping, and has free play at the lever, the spacers are usually the issue.

Once you are sure the clutch is in fact slipping, you'll need to pull the plate and measure a spacer. 1.530 is oem and the can be had .040 shorter and .080 shorter. As the clutch stack wears down, you have to move to a shorter spacer set. And the MoCo was real proud of those spacers, based on the price. Six spacers and new nuts was about $25 back when. Ya, the nuts are single use.

The way we did it back when, was to replace the nuts with nylock nuts and set the plate height by measuring it on the scooter. Measure the stack with the spacers in place, then take the spacers out. Then tighten the nuts until you have replicated the original measurement. The tighten the nuts to shorten the distance about 020-.030. Be aware that there are two fairly cocky springs under that plate.

Also the screws that hold the primary cover on are not Phillips head. Looks like Phillips, but will strip out if you use a Phillips driver. They are posi drive. Takes a different screw driver. Some Allen screws would be a real good investment.
 

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Thanks for the feedback guys. I really appreciate it. I don’t feel any slop “play” in the clutch and the only gear it is happening in is first. It’s got me boggled, I work on cars all the time, but bikes are a whole new ballgame to me. I just wish there were an honest shop near me, I refuse to take it to the dealer. I’m hoping it’s nothing major. The scooter only has 3 thousand miles on her. Everything is original and all matching numbers. Thanks again guys.
At my minds wits,
 

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If you can work on a car, you can work on a bike. Is it slipping or jumping out of gear? Put it in a higher, rev it up and try to take of from a dead stop. If it is the clutch, it will slip then. Get a manual and dig in.
 

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Discussion Starter #7
The way we did it back when, was to replace the nuts with nylock nuts and set the plate height by measuring it on the scooter. Measure the stack with the spacers in place, then take the spacers
If you can work on a car, you can work on a bike. Is it slipping or jumping out of gear? Put it in a higher, rev it up and try to take of from a dead stop. If it is the clutch, it will slip then. Get a manual and dig in.
i put it in 1st gear and can let the clutch out and rev the rpm’s pretty high and she barley moves. 2nd gear no problem. In 2nd, as soon as I let off the clutch and give her some throttle “hang on” we’re going for a ride. Thanks again for the help.
 

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I think you have found the reason it got pushed to the side and left to rot.

It sounds like you have a trans issue, and not a clutch issue. Probably something up with the shifter mechanism, but could be a lot of other things too.

To get at it, the motor needs to go on the bench, be completely stripped down, and the cases split. Big job with lots of hours involved. And when you find the issue, it may require a snipe hunt to find the needed parts.

So now the question is, how much do you want to spend on an old Iron Head?
 

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I think you have found the reason it got pushed to the side and left to rot.

It sounds like you have a trans issue, and not a clutch issue. Probably something up with the shifter mechanism, but could be a lot of other things too.

To get at it, the motor needs to go on the bench, be completely stripped down, and the cases split. Big job with lots of hours involved. And when you find the issue, it may require a snipe hunt to find the needed parts.

So now the question is, how much do you want to spend on an old Iron Head?
Didn't the 80s Sportsters have a trapdoor setup for the transmission? Should be able to work on it without splitting the cases. I think Sportsters had the trapdoor configuration until 2004.
 

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Discussion Starter #11
I'm thinking not, right up till I read this.

If it does, then the job gets a lot easier. Just pull it all out with the trap door.
I appreciate all the input and help. I’ll have to tinker around and see if I can do it or take it to the shop. That wasn’t the reason it got pushed in the barn to rot. My dad was in a very bad car accident and screwed his back up and was never able to ride again. The bike only has 3k original miles on it, everything with the exception of the fat bob tanks that is. He should’ve sold it to me 20 years ago when I asked, but he was stubborn and took it to his grave with him, so to say. Once again, thanks for all the help. 🤘🏻
 

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it has a trap door,,, 4 5/16 × 18 screws behind the clutch basket...

take the sprocket shaft cover off,,, remove the sprocket nut,,,
then
loosen the iprimary chain adjuster,,, an Allen head screw with a lock nut on the lower front of the cover... after its off,,, remove the front sprocket nut,, disassemble the clutch. and there are the 4 screws,,, listen for around 2 dozen bearings to drop out when the trap door moves around 2 inches...

a manual is a great help... or we can talk you through it
.. listen to therm as well,, he is very good with harleys..
 

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Thanks for the feedback guys. I really appreciate it. I don’t feel any slop “play” in the clutch and the only gear it is happening in is first. It’s got me boggled, I work on cars all the time, but bikes are a whole new ballgame to me. I just wish there were an honest shop near me, I refuse to take it to the dealer. I’m hoping it’s nothing major. The scooter only has 3 thousand miles on her. Everything is original and all matching numbers. Thanks again guys.
At my minds wits,
Not even an option. Even if you wanted to, you CAN'T take it to a dealership. They won't touch that bike.
 

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That 1980 Sportster case has a trap door. No need to pull the engine and split the cases.

Back to the issue at hand, so the clutch or something is slipping in first gear and only first gear. Doesn't make sense. You say it doesn't slip in any of the other gears, only first. That implies that you are able to launch the bike and shift through the gears. If the OP is able to launch the bike in first gear and other than a slipping clutch there are no other flags, like grinding noises, then I would surmise that the first gear set and shift mechanism stuff is functioning. I think the OP has either misdiagnosed or is leaving out some key data points.
 

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I didn’t try any other gears above 2nd. I didn’t want to do anymore damage to it other than what is done now. It will move in first but with a lot of throttle and barely moves. After shifting up to second it seemed to ride fine. I’ll ship it UPS to ya so you can check it out,lol. I know when my dad last rode it “many moons ago” the bike had no issues at all. If it weren’t for the sentimental value of it I wouldn’t even mess with it. But my Dad’s last wish was for me to get it running and keep it in the family
 

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The tranny is easy to get in and out. Once you get it out, you can look at it our have someone else look at it. The same tranny was used for a lot of years and aftermarket parts or whole transmissions are available. I doubt you need a whole tranny. I can't figure what would make 1st slip without a lot of other metallic noise.
 

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The tranny is easy to get in and out. Once you get it out, you can look at it our have someone else look at it. The same tranny was used for a lot of years and aftermarket parts or whole transmissions are available. I doubt you need a whole tranny. I can't figure what would make 1st slip without a lot of other metallic noise.
Do you get a good "klunk" when you shift it into 1st? If I was you and did not have the experience working on motorcycles I would take it to an independent Harley mechanic. If you post what town/city you are located in, someone on here should be able to provide some guidance on who may be able to work on it, or at least look it over and give you an opinion on what is wrong. No disrespect; however, trying to diagnose an issue over the internet is like a blind chicken pecking for corn.
 

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I didn’t try any other gears above 2nd. I didn’t want to do anymore damage to it other than what is done now. It will move in first but with a lot of throttle and barely moves. After shifting up to second it seemed to ride fine. I’ll ship it UPS to ya so you can check it out,lol. I know when my dad last rode it “many moons ago” the bike had no issues at all. If it weren’t for the sentimental value of it I wouldn’t even mess with it. But my Dad’s last wish was for me to get it running and keep it in the family

I doubt you are serious, but if you are, I am in Fayetteville, NC. Get that bike into my garage and I will gladly work on it. Has been a while since I worked on an old iron head but I still have all the unique tools to mess with that clutch and transmission. It will be fun. I will work for free, but you will have to cover actual cost of materials. Let me know if you are serious.
 

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I understand your apprehension to shift into higher gears under engine power. A good alternative is to remove the primary chain and with the rear wheel raised, rotated the clutch by hand and go through all the gears. If anything is wrong, it will be blatantly noticeable to your hand on the basket. You should also rotate the basket in both directions, in every geared enough revolutions for each gear set to make several revolutions.
 
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