Hi all, I have a 1992 FXDC Dyna and as far as I am aware it is pretty standard in the engine and transmission dept….at least I haven’t change anything.

A couple of weeks ago there was a crunching sound in my primary, literary as I pulled p to my house. I opened her up and sure enough the Jackshaft starter bolt had come unscrewed ands the lock washer was broken. Everything else appears to be fine so I figured it’s a simple replacement.

I ordered a replacement which was the “Spyke Bolt/Screw kit Item № 13-798” for Big Twins 1989-1993, length: 132 mm; thread: 1/4”-20.

When I try and replace the parts it turns out the new bolt and washers are much fatter than my original and the thread is different. Mine is a lot thinner. The new bolt head is 10mm and 65mm thick shaft and my original is 8mm bolt head and the shaft is 5mm thick.

I tried using their washers and lock nuts with my bolt as it wasn’t broken but when I tightened it there was a lot of slack/movement and to be honest when I put the tab into the Jackshaft there was so much movement that I don’t think it


Tab in the groove

Tab easily comes out of the groove

would stay there for a minute. You can see in the photos and video. It feels like there should be a sleeve in there?

So….any idea whether my original thinner bolts is “original? And more importantly should there be this much slack in the bolt?

Sadly I cannot afford to buy an aftermarket system which might be better.

 

Might try posting this in the Dyna forum. Ken

 

But it sure has a slack problem

 

Throw that New bolt away and use the old one.. You shouldn't have any issues... Do you have a 9 or 10 to starter sprocket drive.. Cuz the old bolt is the new style setup. Did you own this bike from new and maybe somebody upgraded the clutch basket and starter drive?

 

the starter is the small bolt your over thinking it

 

OK thanks hotrod but it does sound counter intuitive though with the newer one being thinner and "weaker". I got the bike 5 years back and theres nothing in the documents that says they changed the starter drive. I'm pretty sure I have a 9 starter sprocket drive (from photos) but i'll need to take off the primary to check (Im working outsides so cant leave her open).

 

Thanks John but i cant understand why they would put a notch at the end of the jackshaft which holds a tab...supposedly so it doesn't spin...and then have a set up which, even when tightened, has so much movement it lets the tab come out of the notch...whats the point of this then?

 

Ive checked the OEM part number 4325 and the measurements I'm getting would match my original "thinner" bolt (which has worked fine since I bought the bike 5 years ago, until now where the locking tab washer broke) my concern was also about the amount of movement it has but I'm guessing as it did somehow work before then that would the way it's supposed to fit? I just don't want to put it all back together and find I've got to open her up again or worse.

 

The replacement locking washer tab and bolt is the wrong one for your set up (as you already know). The inner diameter of that locking washer tab is bigger to accommodate the larger diameter bolt (the wrong bolt). When you put the locking washer on the other original thinner bolt, there is too much play and the locking tab is not locking.

You need the locking tab and sealing washer that matches your smaller diameter bolt. Order the locking tab and sealing washer for a 1994 model year. Use blue loctite on the threads of that long bolt in addition to the locking tab washer. Clean the threads bolt threads and the female threads first. That long bolt only uses very low tightening torque so go easy. I think like 7 lbs of torque.

Also not a bad idea to use hylomar on that tiny sealing washer if you care about keeping oil out of the starter motor.

 

Hi Yankee Dog I think you've hit the nail on the head - bravo! And for the extra fitting details!
I had a look again this morning and I wondered if the parts I received were from another year bike (as HotRod suggested, thanks) and sure enough when I searched the details for OEM 4358A these appear to be the size I have on my bike and they are for a 1994 onwards model, so I guess the PO had changed the Starter motor or Jackshaft section? I can now see if the washer fits my diameter bolt better and once its locked in on the notch this should hold it in place properly.
This also answers my question to HotRod which is that the thinner bolt is actually the more recent version, go figure.
Thank you gents....astounding forum!