stub shaft question

[Jd2859]

hey guys seen a few threads about the bearing in the stub shaft being pushed in towards the motor decided to check mine I can barley fit a .028 feeler gauge in-between the housing and bearing its probably more like .027 but I couldn't find it to check but is it worth taking assembly out and trying to press the bearing in further?

 

[MrSled]

hey guys seen a few threads about the bearing in the stub shaft being pushed in towards the motor decided to check mine I can barley fit a .028 feeler gauge in-between the housing and bearing its probably more like .027 but I couldn't find it to check but is it worth taking assembly out and trying to press the bearing in further?

Where are you measure? Is your offset off?

 

[Jd2859]

Where are you measure? Is your offset off?

Have not checked offset due to only having a 240 tune currently and never blew a belt “1800” miles but plan on being around 300-350hp for next season Just seen a few threads about bearing being pushed in from the factory so just curious if mine is fine the way it is or I should press it in further

 

[Jd2859]

Where are you measure? Is your offset off?

I’m measuring behind housing in front of bearing

 

[SidewinderConvert]

I’m measuring behind housing in front of bearing

Have you measured what your clutch offset is? At 300+ horse you really need to be in the 57.5-58mm range. Take a look at the Thunder Products thread here.

https://ty4stroke.com/threads/lots-of-testing-and-believe-we-have-the-offset-nailed-down.162304/

If you can get your clutch in to that offset and are confident you won't blow a belt I would just leave it be. If either of those are not true press it back in and if you are really worried locktite it in place.

 

[Jd2859]

 

[Jd2859]

Have you measured what your clutch offset is? At 300+ horse you really need to be in the 57.5-58mm range. Take a look at the Thunder Products thread here.

https://ty4stroke.com/threads/lots-of-testing-and-believe-we-have-the-offset-nailed-down.162304/

If you can get your clutch in to that offset and are confident you won't blow a belt I would just leave it be. If either of those are not true press it back in and if you are really worried locktite it in place.

Have you measured what your clutch offset is? At 300+ horse you really need to be in the 57.5-58mm range. Take a look at the Thunder Products thread here.

https://ty4stroke.com/threads/lots-of-testing-and-believe-we-have-the-offset-nailed-down.162304/

If you can get your clutch in to that offset and are confident you won't blow a belt I would just leave it be. If either of those are not true press it back in and if you are really worried locktite it in place.

no I have not yet but I plan to and I’m sure I’ll be machining my secondary to achieve that

 

[Turboflash]

Just posting an FYI in case anyone is interested.

I have seen 3 brand new stub shaft assemblies right out of the Yamaha box. In all 3, the bearing was pressed in to be flush with the back side not pressed all the way in. Either that's the design intent, or all 3 of the new ones I've seen were assembled wrong.

The whole point of this exercise is to ensure the bearing does not move either way.
I know on TCats, if the bearing is pressed all the way in, then the secondary will have to have all of the shims that come with sled when new installed. Could be problematic. With the bearing flush to the back, secondary shimming is right in the middle of the supplied shims.
On Winders, it may actually help get the offset correct.

 

[bleedyamaha]

I am going to have my alignment checked. This is the back side of my primary. Anyone have a pic of the back of there primary that hasn’t been rubbed?

 

[0degC]

Just posting an FYI in case anyone is interested.

I have seen 3 brand new stub shaft assemblies right out of the Yamaha box. In all 3, the bearing was pressed in to be flush with the back side not pressed all the way in. Either that's the design intent, or all 3 of the new ones I've seen were assembled wrong.

The whole point of this exercise is to ensure the bearing does not move either way.
I know on TCats, if the bearing is pressed all the way in, then the secondary will have to have all of the shims that come with sled when new installed. Could be problematic. With the bearing flush to the back, secondary shimming is right in the middle of the supplied shims.
On Winders, it may actually help get the offset correct.

Interesting. So maybe to much worry about bearing being all the way out?

 

[1nc 2000]

Best is to take bearing out and green loctite it in place so the shaft doesn't move when you blow a belt. Its good preventive maintenance.

 

[Turboflash]

Yes. The goal is make sure the stub doesn't move. I don't think it's necessarily critical where the bearing is, as long as one can get offset correct AND it won't move no matter what.