HarleyTechTalk

Technical Forums => Iron Head => Topic started by: 1972XlchBobber on November 12, 2008, 06:18:45 PM

Title: All about transmissions
Post by: 1972XlchBobber on November 12, 2008, 06:18:45 PM
Question concerning new shift fork.  In 4th gear my main shift fork has a slight drag on the counter gear.  It wants to bump bump bump off the gear below.  I have no problem using a file to remove a bit of the shift fork so that it does not rub.  Anyone ever have this happen?  Thanks.
Title: Re: All about transmissions
Post by: nibroc on November 13, 2008, 04:11:23 AM
2nd gear jumps in and out--only problem I've ever had w/my ironhead trans. try real hard not to ride as hard as i used to.
Title: Re: All about transmissions
Post by: help-u2 on November 13, 2008, 12:05:05 PM
they make +  and - offset forks...
make sure yours is not bent
Title: Re: All about transmissions
Post by: saltcaveminer on November 13, 2008, 02:12:20 PM
the shifter fork might not be the problem.make sure the shift rod is not bent or tilted .this rod is usually supported on both ends when installed in the case .it may be off a bit when not supported.check all the clearances as per the manual.Salty
Title: Re: All about transmissions
Post by: 1972XlchBobber on November 13, 2008, 03:05:38 PM


One thing I do not understand, the forks which are sold over and under dimension.  What exactly are they modifying?  Thanks, Mike
Title: Re: All about transmissions
Post by: fulldress79 on November 13, 2008, 05:18:52 PM
They are adding or subtracting the distance between the shift cam pin and the fork.Moving the shifting dog
Title: Re: All about transmissions
Post by: 1972XlchBobber on November 13, 2008, 05:52:53 PM

Thanks for all the responses, this web site already kicks butt.  And I really like the spell check.

I just took a look at my new shift fork from V-Twin as compared to the OEM fork.  The V-Twin is dimensionally higher on the bottom and thus has a slight interference with the counter gear. It it very high as compared to the OEM.  I will try removing some material and I should be good to go.

~~~~~~~~~~~~

One last question:

The forks slide up and down on the "fork post" for lack the proper item description.  Should my fork post be press fit into the trap door?  Mine is loose, slides easily in and out of the trap door.  I can loctite it in but the risk is that it would be out of square.  Thoughts?
Title: Re: All about transmissions
Post by: fulldress79 on November 13, 2008, 06:08:53 PM
Yeah it should be tight. Can you wiggle it in the hole? If it doesnt' wiggle you may get away with locktite. BUT if it were mine I'd replace it for piece of mind,Sometimes they go cheap on eBay. A Sportster begs to be ridden with spirit! You don't wanna be be gettin in it and not have confidence in it.
Title: Re: All about transmissions
Post by: fulldress79 on November 13, 2008, 06:10:47 PM
I meant "gettin on it"...Youve already gotten into it! :up:
Title: Re: All about transmissions
Post by: fulldress79 on November 13, 2008, 07:05:34 PM
 BTW by replacing it,I meant the trapdoor :bf:
Title: Re: All about transmissions
Post by: saltcaveminer on November 15, 2008, 12:37:49 PM
roll the rod on a flat surface (like glass)if it doesnt click use itsame goes for pushrods btw.Salty
Title: Shifting Fork Rollers
Post by: 1972XlchBobber on November 18, 2008, 07:06:55 PM
Something I missed on my rebuild.  I received this bike with the transmission in pieces. As I re-assembled I failed to notice there are small caps that fit on top of the shift forks.  The caps slide up and down within the shift cam.  They take up a lot of slack in the free play when the gear is not being used.  I thought I had too much free play and was discussing this with local Z&M HD dealer in Greensburg PA.  Cudos to Jeff the parts guy who asked me about these rollers.  And then I discovered I was missing parts on my rebuild.  The manuals and parts guides are tough to follow, no excuse, I'm just happy I'm this much closer.
Title: Re: All about transmissions
Post by: saltcaveminer on November 19, 2008, 01:45:43 PM
yes there are shifter fork rollers.aka tophats.Salty
Title: Speedometer gear
Post by: 1972XlchBobber on December 02, 2008, 06:34:56 AM
Someone plugged the speedometer gear hole on my 1972 ironhead.  When I insert the counter low gear with the speedometer gear on it there is a bit of interference with the plugging material.  The interference goes away if I put a big spacer on the low gear.  Unfortunately the spacer is too large and prevents the counter gear from spinning.  I just gave the spacer example to provide visualization.

I considering removing the spiral speedometer gear from my counter low gear.  Has anyone ever done this?  What does the back side of a 1973 counter Low gear look like?  Is it a flat surface? or is there a cup of some sort to catch oil on the back side?

Thanks, Mike
Title: Re: All about transmissions
Post by: saltcaveminer on December 02, 2008, 01:23:47 PM
the 73 countershaft low gear will fit .i have one in my 70xlch.in my situation a reinforcing ring was added to the shaft/bearing boss.(could not fit the speedo gear anymore.)the stock speedo gear can be machined off, also the speedo block off plug can be ground down a bit iif its threaded.Salty
Title: Re: All about transmissions
Post by: 1972XlchBobber on December 02, 2008, 02:40:45 PM
Thanks for you help Salty, As I look at this gear. It looks like the spiral is press fit onto the toothed gear. That the toothed gear is machined as one piece.  I'm thinking of chucking the toothed gear in the lathe.  Cutting the spiral off by putting the tool at the id of the seam between the spiral and the toothed gear.  Not sure what will remain. 

Should I machine it flat or leave a bit of a cup that fits around the bearing boss?  I'm not sure which would collect more oil and send it into the bushing.  Flat Face or Cupped?

Thanks, Mike
Title: Re: All about transmissions
Post by: saltcaveminer on December 02, 2008, 03:36:21 PM
i think flat cause you need to add a thrust washer between the gear and the bearingSalty
Title: Re: All about transmissions
Post by: 1972XlchBobber on December 05, 2008, 09:13:42 PM
OK, I have the transmission in the case.  End play specs are nice, shifts into all gears nicely except...

With no rear wheel motion:

From 3rd into 4th: If gears are lined up, the shift takes place without any issue.  The gear slides 100% into the mating other.

If the gears are not lined up, the gear slides over and of course cannot intermesh with the other gear (not lined up).  The shifter cam sits at top dead center and does not slide down the other side even when the gears are moved into the proper position.  So I have the cam stuck at top dead center issue.

If the wheel is moving and I hold the lever up until the gears are lined up then there is enough force on the cam that it pushes over just as soon as the gears line up.

Does my tranny have an issue or is this normal?

Thanks, Mike