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Discussion Starter #1 (Edited)
Quick question Gents

Riding today and on the way back home I notice what felt like my Road Star was slipping when accelerating. This was only occurring in top gear when I was trying to go around a car or suddenly speeding up. While taking off at lights etc I never had any issues.

1 - could this be the clutch even though I'm already geared out ?

2 - any chance I could adjust clutch and correct it ?

I don't mind doing a clutch repair however not sure I want to do any type of engine repair

Thanks Gents
 

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the clutch usually starts to slip in the highest gear because that is when the clutch has the most load on it

the clutch is between the engine and transmission, so in 1st gear there is less load (torque) on it compared to 5th gear.

If a clutch with a cable is not properly adjusted it will slip when there is no more free play. I dont remember if the Road Star has a hydraulic clutch, they are not usually adjustable.
 

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Road Star bikes have a clutch cable (not hydraulic link) so... yes they do need to be adjusted to maintain the freeplay as the clutch plate thickness slowly wears down

as the clutch wears the point on the grip lever where the throwout bearing contacts the clutch plate moves further and further away from the rider (outwards). If you dont keep adjusting the freeplay back in eventually the clutch will slip

think of it like this - the clutch grabs backwards from you grabbing the lever - when you grab the level the plate un-grabs the clutch plate. As the clutch wears thinner it has to 'un grab' the plate further away from you, which means the clutch level in your hand has to go further out.

Dont think about it too long or blood will start gushing out of your nose. Its hard to visualize because its the opposite of what you are doing with the lever in your hand.
 

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Discussion Starter #6
Great stuff ! As usual KCW


Road Star bikes have a clutch cable (not hydraulic link) so... yes they do need to be adjusted to maintain the freeplay as the clutch plate thickness slowly wears down

as the clutch wears the point on the grip lever where the throwout bearing contacts the clutch plate moves further and further away from the rider (outwards). If you dont keep adjusting the freeplay back in eventually the clutch will slip

think of it like this - the clutch grabs backwards from you grabbing the lever - when you grab the level the plate un-grabs the clutch plate. As the clutch wears thinner it has to 'un grab' the plate further away from you, which means the clutch level in your hand has to go further out.

Dont think about it too long or blood will start gushing out of your nose. Its hard to visualize because its the opposite of what you are doing with the lever in your hand.
 

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Its a fairly simple adjustment - on some bikes you loosen the cable down on the engine end to get more freeplay, on others it up by the grip

its a good time to make sure the cable slips freely, then lube it anyway with white lithium spray. I forgot to mention that, if the cable is hanging up that will keep it from grabbing fully and cause it to slip.
 

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Discussion Starter #8
So you think I should start with the clutch handle adjustment first ?


Its a fairly simple adjustment - on some bikes you loosen the cable down on the engine end to get more freeplay, on others it up by the grip

its a good time to make sure the cable slips freely, then lube it anyway with white lithium spray. I forgot to mention that, if the cable is hanging up that will keep it from grabbing fully and cause it to slip.
 

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Another thought, have you recently changed oil, if so different brand or weight. I always had used Mobil 1 20w-50 full synthetic motorcycle oil, bought some Valvoline Motorcycle 20w-50 that was on sale. I had same issue you are having. I adjusted cable and it did get better. At next oil change went back to Mobil 1 and issue went away. Most will say it was coincidence, but the slipping clutch in fifth gear went away and never came back.
 

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Discussion Starter #10
I only use Mobile 1 20/50 however I did check it about two weeks ago and it wasn't full but oil looked like new so I was going to wait and change it.

I did 4qts, 3 first and then started bike so it would suck down the 4th, never went back and actually checked it as you have to ride and then pull seat off - sounds like my ass was just lazy after typing this out lol


Another thought, have you recently changed oil, if so different brand or weight. I always had used Mobil 1 20w-50 full synthetic motorcycle oil, bought some Valvoline Motorcycle 20w-50 that was on sale. I had same issue you are having. I adjusted cable and it did get better. At next oil change went back to Mobil 1 and issue went away. Most will say it was coincidence, but the slipping clutch in fifth gear went away and never came back.
 

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I think I have the Road Star factory service manual on this computer - I was able to find the free PDF download version when I was thinking of getting a Road Star last fall

if you trace the clutch cable down to the engine, usually there is a lever there. If you push it in the direction the cable will pull it there should be a little bit of free play until you feel it hit the throwout bearing, then it gets really hard to move it any further, because you will be compressing the clutch spring.

If you cant feel any free play, then loosen up the lock nut at that end, the loosen up the knurled bolt the cable goes thru until you get a bit of free play, then tighten up the lock nut snug.

There is usually the same set of adjustments at the handlegrip lever, but with less adjustment range. Its possible to max it out in one direction on the grip end, that is why its adjustable at both ends.

On some bikes you have to adjust both ends, but I dont understand why that is.

You can get the operators manual for all Vstar bikes for free, because they are free anyway. The clutch adjustment should be in the owners manual, and the service manual PDF online.
 

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I just looked, I only have the owners manual for Road Star

its says to loosen the adjustment at the grip-lever end first to get more freeplay. If you cant get enough adjustment at that point, there is an inline adjustment half way down the cable (about level with the cyllinder head) - there is no lever down at the engine end, apparently the cable goes straight into the engine block.

But its the same idea, when you push the clutch lever at the grip with your fingertip, it should move very easy (freeplay or slop) until you feel it hit the throwout bearing in the clutch, then it gets harder to push further. That freeplay should be at least 1/4" at the end of the lever as it moves.

If there is no freeplay, that is why your clutch is slipping.

Les is also correct, if you used a car motor oil with modified mpg enhancers (more slippery than standard oil) that will also make your clutch slip, because a motorcycle clutch is in the oil bath.

there way to tell if oil is ok for a motorcycle, look at the SAE lollypop logo on the bottle, the bottom half of the outer circle must be blank. Google this if its not clear.
 

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Here's screen shot of repair manual, down load free one if you don't have one. I would try this first. Looks really easy. It's easier than my 1100.

 

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KCW, we make a pretty good team. you do the typing and I do the pictures within minutes of each other. We have done this several times in the past. Pretty cool, like minds.
 

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Discussion Starter #16
Guys, I was able to use the knowledge and diagram you both provided to tighten up the clutch and after a 4 hour ride yesterday I would say it's fixed.

I don't know who is Robin or Batman but you are both Heros lol

Thanks !


KCW, we make a pretty good team. you do the typing and I do the pictures within minutes of each other. We have done this several times in the past. Pretty cool, like minds.
 

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I think you intended to say "adjust the clutch" and again its weird because the clutch lever works backwards, when you pull the lever it un-clutches the engine from the transmission. When the cable is loose the clutch is tight.

to be clear, you now have some "slop" on the lever when you are not pulling it, now you can wiggle the lever end in and out freely a bit, yes?
 

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