A Hub that Isn't True

[plumcrazy]

Hi Gentlemen!

Need a lesson on hub's, in our case the rear or our 47 knuckle..All parts are original.

Me and my son Avery are working through our new bike page by page in the service manual. We were making sure that the rear tire was centered and not angled. The service manual says to measure from the rim to the inner chain and should be be approx 1-3/16. To get this we were hitting our chain guard with the chain on the top right. With some messing about we noticed that the hub itself isnt true.

Sorry if not explaining this properly, but with me in the back of the bike and it on the center stand, turning the tire forward, we take a small level against the hub on the right side, throttle side. With the bubble in the middle, we can can clearly see that with a full turn the hub isnt straight. It has at a low point bout 1/8th-3/16 gap.

Whats the best way to remedy this? Can we set up our dial indicator where it is and start to "true" it with the spoke adjustments or is it best to take off and do it? I can take pics if it helps.

Thanks guys!

Kurt

[1950Panhead]

Me and my son Avery are working through our new bike page by page in the service manual. We were making sure that the rear tire was centered and not angled. The service manual says to measure from the rim to the inner chain and should be be approx 1-3/16. To get this we were hitting our chain guard with the chain on the top right. With some messing about we noticed that the hub itself isnt true.

If fender is original and tire is original 5x16 size align tire in center of fender towards front, there is minimal clearance.
If chain hits guard bend guard up so it clears, if that fails you may have a replacement guard or other parts have been changed.

Spin the wheel and watch the rim, if rim moves left or right or up and down then wheel needs to be trued.

[Jerry Wieland]

If the hub is bent the wheel has probably been in an accident. I have straightened the right/star side of a star hub but never on an assembled wheel. I put them between centers and hit them with a lead hammer that I also use to true flywheels. If they are bent a lot I throw them away. I think if you try to straighten the hub when the wheel is assembled you will knock the rim out of true. If the left/drive side is bent the hub is junk.

Jerry

Hi Gentlemen!

Need a lesson on hub's, in our case the rear or our 47 knuckle..All parts are original.

Me and my son Avery are working through our new bike page by page in the service manual. We were making sure that the rear tire was centered and not angled. The service manual says to measure from the rim to the inner chain and should be be approx 1-3/16. To get this we were hitting our chain guard with the chain on the top right. With some messing about we noticed that the hub itself isnt true.

Sorry if not explaining this properly, but with me in the back of the bike and it on the center stand, turning the tire forward, we take a small level against the hub on the right side, throttle side. With the bubble in the middle, we can can clearly see that with a full turn the hub isnt straight. It has at a low point bout 1/8th-3/16 gap.

Whats the best way to remedy this? Can we set up our dial indicator where it is and start to "true" it with the spoke adjustments or is it best to take off and do it? I can take pics if it helps.

Thanks guys!

Kurt

[plumcrazy]

Thanks guys! I just made a quick video of me measuring the rim by way of dial indicator as it turns. It measures about .4 out at the highest point. Whats acceptable and is the way to fix this loosening 3-5 spokes on the low side and tightening the 3-5 on the opposite site?

Last thing, swear! The service manual says 1 3/16th inch from the inner chain link to rim to make it square in the frame. I put a dial indicator on the rim @0 and went to one side, pulled it out .3 and back to the other side and pulled it in to 0 till i had .5 play in the chain. Hope this is acceptable since the manual isnt that exhaustive in defining how to do it...

Heres the video, thank you again!!

https://youtu.be/4AnpZ6_DGuY

[BigLakeBob]

I would say if the hub needs fixed it should be fixed in the un-spoked condition if the flanges are not true. Easy to do, I made a plate with a center hole as big as the inner hub diameter, then sawed the plate in half, I then slip it under the flange that is bent, put feeler gage under the side that doesn't need adjusted and press away. After several attempts you will get it true. Spin it on an axle and check with your dial indicator to find the high or low spot. A quick view of your video shows me the rim is all out of wack with a constant .030-.060 back and forth. Un-spoke, fix the hub and go for it again in my opinion.

[plumcrazy]

I would say if the hub needs fixed it should be fixed in the un-spoked condition if the flanges are not true. Easy to do, I made a plate with a center hole as big as the inner hub diameter, then sawed the plate in half, I then slip it under the flange that is bent, put feeler gage under the side that doesn't need adjusted and press away. After several attempts you will get it true. Spin it on an axle and check with your dial indicator to find the high or low spot. A quick view of your video shows me the rim is all out of wack with a constant .030-.060 back and forth. Un-spoke, fix the hub and go for it again in my opinion.

Thanks Mr Bob! I know your right and going to give it a shot! Never done it before but found a few videos online that were useful so will be posting a result one way or another soon, ha! Thanks again.