Starter reduction gear. Cracked case? How to fix…..

’94 vfr went to start her up the other morning and git 1 turn over then a horrible CLUNK sound. And she would turn no more. Pulled the clutch cover and looked around, things seemed to spin freely. But the starter reduction? Gear was a bit wobbly . Pulled the starter clutch and found the center pin for the gear that rides between the starter and the starter clutch was loose, pulled the gear and low and behold the pin as it was set into the engine block had a corner broken off its locating hole. F’cking weird. How the hell does this even happen and 2nd how the hell can this be repaired? I have the broken piece luckily nand it fits back into place sooooo some sort of aluminum welding ?
Has anyone ever seen this >?
And ideas on how to repair ?

 

That is seriously NOT GOOD. I don't think that is repairable, at least not with the engine assembled. I have never seen that before. Has your starter clutch ever made grinding / crunching noises or protested when cranking?

 

The crack started @11 o’clock and there’s a mark in the crankcase going vertically from it, a possible crack?

 

Likely just a casting artifact.

 

Dang, that looks ugly.

Complete uninformed speculation on my part, but perhaps your engine was hydro-locked from fuel leaking through a carb and partly filling a cylinder? And the casting that broke just happened to be the weakest point in the chain between the starter and the cylinder.

 

The starter has been very quiet, no grinding or cracks in the starter clutch, i replaced it about 2 years ago.

The mark you see at 11o’clock isn’t a crack, perhaps a casting mark.

Done tell me it’s unfixable? Im not just gonna dump this biker now. There’s gotta be something I can do?
Worst case scenario I’ll JB weld that small piece back on and slide the pin back into its hold. What have i got to loose? Right ?

 

That it breaks off again, goes thru some primary gears to get chewed up and sends debris thru-out your engine?

I bet if you tried JB Weld, started it one time and then removed the cover, it would be broken again. I think that is too much force / stress for epoxy of any kind.

So... why did you replace the starter clutch? Perhaps what was happening to make you replace it was also responsible for the original damage.

 

With the pin engaged in the crankcase, mark the shaft with a sharpie at the lowest point of the break. How much of the shaft is into the crankcase?

 

The more I think about this, I am heavily leaning towards something happening when the crankcase cover was off. When assembled, the pin is engaged and supported on both ends. Pretty much the only way it could crack off the case in that manner is if it wasn't supported/located by the case cover.

Perhaps when the starter clutch was worked on or when the clutch plates were replaced (twice?).

If the pin still has a decent amount of purchase in the case, I would assemble (without the broken piece) and not worry about it (mostly). I might put a thin thrust washer behind the gear against the broken area, ensuring there is still proper gear alignment and no binding.

 

I will do that today, and reply with my results.

 

I did not realize the pin was supported from the covers side as well. That makes me believe this thing is salvageable.

 

I replaced the starter clutch about 2 years ago (20,000miles) because it was cracked and gave me intermittent starting issues. I’ve had zero starting issues since then. The starter clutch currently looks fine FYI,.

 

Here’s some more pics of the pin and marked the edge were it meets the case. Also just for my own satisfaction I took a pic of the pin in the cover. Im gonna remove true token piece and put the thing back together and probably just cross my finger now every time I start this baby.
But Sill I wonder how did it breaks to begin with?

 

Will likely be ok.

I am still of the opinion it happened sometime the cover was off, it seems the only way the pin could be forced off center and crack the case in that manner. Or perhaps installing a stubborn cover not knowing that the pin has to engage it was well.

Good luck.

 

I drove 20k miles with no issue. just randomly one day she made one turn and clunk.!
so i’ve reassembled the engine making sure the pin was in its proper place.
the bike started fine…. like 4-5 times then it happened again! this is very upsetting :-( is my engine block toast because of this??

thank good i just bought a 99 vfr

 

To break the piece off there was have been a bending moment in the pin, in which case the hole in the engine is not perfectly circular, you should be able to feel any slop in the fit
If this is the case then you could ream the hole out by a few thou and fit a bush in or make a stepped pin on a lathe
I am clutching at straws tho

 

Alright, on to the fixing this thing part.
JB weld will absolutely not work. Also welding in the little broken piece will not work. The heat distorts the hole the pin needs to sit in and it's not really very strong.
Your best bet is to TIG weld with the appropriate metal rod enough material onto the casing so you can redrill the hole. A few things to look out for are: take very precise measurements before welding of where the center of the hole should be. Use markings on the casing so you can always find that centre. Use a small drill bit for your pilot hole and make the hole progressively bigger. That way your centre stays in the same place. Its really difficult to drill straight (enough) with this casing onto tour bike but you'll manage. Also before welding and drilling take note on the depth of the hole and hight of the stump. After welding the stump will be irregular and lumpy but with some patience and a dremel tool you will be able to get it flat (enough) again. Best to try and salvage a little bit of the old on the left side for reference.
I know it's not ideal and maybe a bit of a bushfix but it's the only way to do this without taking the engine out and apart. That offcourse would be the best way. Then you could use a bench drill and a lathe and you could work within the required tollerances.
Good luck!