Gouge in cylinder

[Cooldean69]

Alright… bummer. thank you anyway, I’ll probably just save up to get the whole kit online with jugs and pistons and stuff maybe a month or two.

[Dragstews]

Sorry Man ....
Didn't know the jugs was in that shape until the hone showed the bad ...



This is V-Twins re-pop kit ..
It's std. bore and are a good re-pop of what once was ...
Got many Sporties on the road using em with no problems ...

If you can't find a V-Twin dealer in your area, I can dropship a kit to you ..
____________________________________

Wait just a dad-gum second ...

Which jug do you have that's screwed, front or rear .. ??
We may still get you back on the road without the need to make a run on the bank ...



Here's the rear jug ... Looks as good as new ..
Both .030" over pistons are in grand shape ...

[flatman]

Drag, kudos, you are a straight shooter, scholar and a damn fine gentleman.

[Dragstews]

I have my moments ...

(Could have sumthin to do with being a "Lewis", it's a Masonic symbol)

[Cooldean69]

Yeah it’s the rear what do u want for just the one?

[Cooldean69]

Here is something I read on another forum, what are your thoughts on this everyone


maybe I can shed some light on this. I am willing to bet that this happened on the rear cylinder. Now, a defective/improperly installed wrist pin keeper will usually go south less than a few thousand miles. What causes this problem in 99% of the cases I have seen is the connecting rod races/rollers/crankpin going south. The torque is applied to the sprocket shaft side of the flywheel assembly. As rod bearings wear from this torque they wear predominately on the sprocket shaft side. Since the rear rod is a forked rod and has left and right side bearings and about half the size of the front rod bearings, the wear will cause the rear rod to **** to the left. This cocking forces the piston and wrist pin to the left and pushes the wrist pin against the retainer. Now, spirolock retainers are a lot harder to dislodge than an internal snap ring but it is only a matter of time before they do. When you pull the cylinder, check the vertical and lateral movement of the rod assembly and I think you will find this is the culprit. I take no pleasure in someone elses misfortune, but at least you didn't blow a hole in the cases.

[Cooldean69]

It would suck to split the cases is this something I should be concerned about? I haven’t even pulled the cylinders yet hopefully tomorrow I can give everything a good inspection

[Dragstews]

The owner said he doesn't want to spit up the set ... (Future plans for the critters, guessing ?)
But if you want the set for $150, the deal is still on ...

BTW ....

I'm just the middle man here, really don't have a dog in this fright ...

Your Hee-Hawing with a Fellow in Sweden ...
(Trade Wars are not in effect with that Country) .. YET .. Lol

[JBinNC]

Here is something I read on another forum, what are your thoughts on this everyone


maybe I can shed some light on this. I am willing to bet that this happened on the rear cylinder. Now, a defective/improperly installed wrist pin keeper will usually go south less than a few thousand miles. What causes this problem in 99% of the cases I have seen is the connecting rod races/rollers/crankpin going south. The torque is applied to the sprocket shaft side of the flywheel assembly. As rod bearings wear from this torque they wear predominately on the sprocket shaft side. Since the rear rod is a forked rod and has left and right side bearings and about half the size of the front rod bearings, the wear will cause the rear rod to **** to the left. This cocking forces the piston and wrist pin to the left and pushes the wrist pin against the retainer. Now, spirolock retainers are a lot harder to dislodge than an internal snap ring but it is only a matter of time before they do. When you pull the cylinder, check the vertical and lateral movement of the rod assembly and I think you will find this is the culprit. I take no pleasure in someone elses misfortune, but at least you didn't blow a hole in the cases.

Part of this explanation is spot-on and part of it is full of shit.

Yes, if the rod rollers on one side of the rear rod go bad, that will cause a side thrust at the top of the rod, and that will knock out a wristpin keeper and cause the subsequent damage to the cylinder. I have seen this exact scenario many times on both Sportsters and big twins. Damage to the front rod rollers can have the same effect, but it is more common and more pronounced on the rear because of the roller arrangement on the rear rod.

The full of shit part of the above explanation is the torque on the sprocket side gobbledygook of crap given as the reason it happens. Disregard that.

These bearings go bad mainly because a partical of dirt or metal gets to the bearing and causes a microscopic bit of damage, and over time the bearing rollers, the shaft, and/ or the race start spalling off bits of metal until failure results. An overload of the bearing, usually by detonation, or heat from a lack of oil will also trigger the same process, but bearing failure is the result.

(This is the best argument for a good oil filter on the earlier pans and knucks, and the reason the evos with their good spin-on filters seem to last so much longer than the earlier motors while delivering more power.)

C, you do need to get the cylinder off and inspect the damage, but also look for the cause. If the rod rollers are bad, it's pretty much game over for that motor. It's too bad, but old motors don't run forever.

Jim

[Cooldean69]

Yeah there might be some wear on this what do you guys think lol





The sketchy part is that clip s just gone I guess the engine was hungry.
As far as checking the flywheel assembly I’m not exactly sure what I’m looking for, rod has a very slight lateral movement I will check the book to see if there’s a spec, any advice would be appreciated.

I am still interested in purchasing your pistons and cylinders drags, but let me first make sure I’m not totally fucked on the flywheel I’ll shoot you an email in a few

[JBinNC]

One easy way to diagnose a failed/ failing bearing in an H-D motor is to examine the piston skirts. Particles embedded in the skirt are evidence of a bearing coming loose somewhere.

From your pics, your piston is galled badly, and a top end rebuild will probably not solve your problems, and will be money and effort wasted.

Jim

[Dragstews]

... Make an offer ...

But, not just yet ...
Pull the jugs and do some investigation ....

Well, looks like I'm a bit late with that advice ...
_____________________________________

All-right ... Here's my thoughts with what you have going on ...

First off is the age of that scooter ..
With mega miles on the old girl, it's bound to have lots of ware on all moving parts ...
But, could have seen a complete rebuild back into the history of it .. ??

Now that you have a piston seizure throwing all kinds of metal down into the motor, a super clean up is really needed to be done ...

All that contamination will head to the oil pump ..
On that year model Sportie the pump has a screen to stop large pieces of crap getting to the return gears .. That's a plus ... Later spur gear XL's motors didn't have that screen
..

That is where you'll find pieces of the wrist pin clip ..
All chew up right at the arresting screen ...
Bit of a chore to pull the pump off ..Dang near need to take the motor out of the frame to gain room to drop the pump from the motorcase ...
Cam cover will need to come off too ..

About the cam cover ...
There are bushing for the cams, pinion shaft and gen idle gear that most likely are toast and will need to be replaced ..
That job is a major chore due to the need for special tools for line reaming the new bushings ...

Have a look at this thread for a detailed look at what all is involved ...
... /// http://www.chopcult.com/forum/showthread.php?t=50289 \\\ ...

As I said earlier, this may have been addressed in the service work that was done years back .. That is, "if" it seen a motor rebuild .. ??

[Cooldean69]

Haha this sucks
I have two crusty flywheel assembly’s sitting on the bench I guess it’s time to figure out how to rebuild one
Drags I will eventually need new pistons and jugs so I guess I might as well buy yours are you still trying to sell
What other stuff should I check while I have this apart, Jim’s pretty much always spot on so I would lay money on splitting the cases, but if I dont have to that would be way better. are there other tests or measurements I can do to ensure I need to pull the crank, it does spin very freely without binding but I’m sure a very small problem when run at high rpms creates rapid wear

[Cooldean69]

Ok thank you for the advice. Yeah it’s a bit of a mystery bike got it off Craigslist, sits really low so yes oil pump is going to be difficult access

Sounds like a total tear down
I will be busy…

[Dragstews]

The jugs & pistons that I have will get that part of the engine back to good ..

Might not have the need to spit crankcase ....
You can flush the case with kerosene a few times ... There should be a drain plug at the bottom of the case flywheel cavity ..
The cam cover/oil pump is a must do, no choice but to take it off for the clean up to happen. Compressed air will be your friend ..!!