would replacing the stock breather with the s&s reed breather valve cause oil pressure to drop? dash light starts to flicker on/off when the bike warms up, applying throttle shuts the light off, but as bike gets hotter light then stays on.

1993 FLTCU 80 in with ev13 cam, s&s reed breather, stock pipes with no name slip ons, pretty sure carb is stock but haven't torn into it yet to verify - everything else was stock on the bike when I got it though.
running fresh maxima 20-50 vtwin mineral oil

cleaned the oil screen at oil change a couple weeks ago - had the motor torn down and split apart for other issue. Less than 10 miles on the oil change. I will check the oil screen again tonight just to make sure the new cam/lifters are not self-destructing and clogging it with metal shavings.

Any other thoughts on cause or things to check? Should I rebuild the oil pump just because (looks like kit is under $20)? The bike showed 72k miles when I got it. I am pretty sure it was completely stock but no idea. Tore it down and pretty much went through everything but the oil pump, never removed that from the cases when I had it apart.

Also, I have no idea how the bike ran before. I got it running but never rode it before I tore it down and started fixing all the obvious issues with it, was still snow on the ground then.

 

No but the first chance you get to replace the reed with a normal gear, do so. Don't waste money on an aftermarket oil pump - stock is as good as it gets.

Number 1 cause of low oil pressure is worn tappet guides. Cheap lifters can add to that as well..

 

I put in hylift johnson which seemed to be highly recommended here and on other forums so hopefully they aren't considered cheap lifters. Ones I took out were stockers in really good condition. Lifter bores and blocks felt good/tight but I didn't bore gauge them. The stock breather gear was in good shape too, I can put that back in whenever I open up the cam gear cover again... heard mixed feedback regarding the oem gear and the reed valve, probably should have just put stock one back in and saved $160 - some lessons I learn the hard way.

I didn't plan on spending $500 or so on an aftermarket pump, but probably won't hurt to rebuild the stocker and inspect the gears in it. The james gasket kit is pretty cheap, looks to have everything except a new spring.

 

Just a thought

https://www.google.com/search?q=bail...t=gws-wiz-serp

 

Oil pump kit is only gaskets and keys and shaft seal. Any "hylift johnson you bought in the past 4 years are counterfeit and very low quality. Johnson hasn't made Evo tappets in 5 or more years.

Again, nothing wrong with the stock oil pump. Replace the tappet guides and use only OE or S&S lifters and you oil pressure issues will disappear.

 

Check, then double check yer check ball...Just went thru that very thing..for some reason the check ball could hardly be coached off the seat..Quick check with a magnetic screwdriver..simple and Fast! Then..I had to hone the seat ...aggressively.. Dunno what Happened, but, assume some one decided to use a Hammer to "reseat" the ball..Bike had a bad Former Life!!!

 

You sure? I just bought a set about a year ago.. And a set couple years before that.. I understand Covid may have them hard to get..

WFO Larry has them..

https://www.larrysmotorcyclemachine.com/lifters.html

 

these were not johnson lifters, they were hylift johnson from larrys machine shop, not sure if that matters? Many recent posts on various forums claimed they were good lifters. Is Larry a scammer that is selling knock off chinese garbage? If so, I can order new lifters and stay away from his stuff. I don't want some garbage in my bike that is going to fail and cause me headaches and $$.

I thought I did my research and was getting quality parts for a reasonable price.

EDIT: disregard my rant above please -



https://www.facebook.com/permalink.php/?story_fbid=916399620486318&id=100063488652744

 

I'd put a mechanical gauge on to sense oil pressure. Go from there..

 

Larry sells good quality from everything I've heard for a lot of years. But they're not Johnson. Best to ask the man himself.