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Author Topic: Oiling piston rods  (Read 2884 times)

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Offline The Gurg

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Oiling piston rods
« on: February 17, 2020, 06:31:55 AM »
Just got the cases back together. I’ve applied assembly lube on anything and everything. I did not remove the piston rods from the crankshaft so I wouldn’t have to worry about finding new bolts. I’ve read once those bolts are removed you have to replace them.

So there is no assembly lube on the inside of the piston rods. What is the best way to oil these. Can I just liberally coat them from the outside with normal weight engine oil once the oil pan is back on?
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Offline bryanj

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Re: Oiling piston rods
« Reply #1 on: February 17, 2020, 07:03:19 AM »
Where is this myth that new bolts are required comming from.
A STANDARD motor rod bolts can be reused as they are torqued not stretched. IF  you highly tune the motor, which usually means new rods anyway, new bolts and nuts may be worth it
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Offline Don R

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Re: Oiling piston rods
« Reply #2 on: February 17, 2020, 07:05:29 AM »
 Torque to yield bolts must be replaced every time. These old bikes don't have those. I like to pre-lube the motor through the oil galley on the right side of the motor, but that's probably overkill.
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Offline The Gurg

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Re: Oiling piston rods
« Reply #3 on: February 17, 2020, 08:11:05 AM »
ok, seems like I got some bad info on these being torque to yield and they aren’t. I don’t remember where I got the info. Appreciate you guys setting me straight.

Calj737 said oiling the rods is unnecessary. Won’t the rods wear before the engine gets pressure? Assuming Calj737 is correct, I’m good to go then?

Don R this is that galley pictured, right? At what stage of assembly can I use the oil galley (without oiling the garage floor), do I need side covers on, jugs and head installed? What is the process you use? Guessing I put the bike on gear and spin the final drive while adding oil? How much oil?

Next rebuild I’d optimally pull the rods and apply assembly lube?
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Offline 69cb750

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Re: Oiling piston rods
« Reply #4 on: February 17, 2020, 08:29:39 AM »
Quote
Won’t the rods wear before the engine gets pressure?

Quote
Don R this is that galley pictured, right? At what stage of assembly can I use the oil galley (without oiling the garage floor), do I need side covers on, jugs and head installed? What is the process you use? Guessing I put the bike on gear and spin the final drive while adding oil? How much oil?

Quote
Next rebuild I’d optimally pull the rods and apply assembly lube?

Remove spark plugs, run starter a few seconds until oil light goes off if you want.
I usually just start engine, oil light goes off in a few seconds.
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Offline The Gurg

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Re: Oiling piston rods
« Reply #5 on: February 17, 2020, 08:50:23 AM »
Ok, awesome. I appreciate all the advice guys! Really great community here. Helping me get through my first rebuild.
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Offline The Gurg

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Re: Oiling piston rods
« Reply #6 on: February 17, 2020, 11:16:56 AM »
Yeah, Calj737, I was hoping some oil may get to the rod bearing. But you’re right, I’m sure. I’d essentially wind up futility oiling the rod frame.
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Offline dave500

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Re: Oiling piston rods
« Reply #7 on: February 17, 2020, 11:37:50 AM »
id be taking the rods off the crank and blowing compressed air through the cranks oil passages,assemble it all as it came apart.
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Online jaytee-nz

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Re: Oiling piston rods
« Reply #8 on: February 17, 2020, 11:56:01 AM »
So just to be clear - the rod bolts do NOT need to be replaced if they have been unbolted ?
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Offline 754

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Re: Oiling piston rods
« Reply #9 on: February 17, 2020, 11:58:32 AM »
You will be fine.
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Offline dave500

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Re: Oiling piston rods
« Reply #10 on: February 17, 2020, 09:14:53 PM »
re use them,no worries.
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Offline disco

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Re: Oiling piston rods
« Reply #11 on: February 17, 2020, 10:16:27 PM »
I’ve re-used rod bolts on 2 rebuilds. An 836cc build and a 0.5mm oversize build. Both have worked fine for me. No rods letting go, smashing through cases or anything like that.

Ps I also use Don’s method of oiling through the gallery. That’s in addition to the normal oil pump priming.
« Last Edit: February 17, 2020, 10:18:54 PM by disco »
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Online jaytee-nz

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Re: Oiling piston rods
« Reply #12 on: February 17, 2020, 11:56:17 PM »
Thanks guys - just saved quite a few bucks !
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