Some of my Mitchell reel have clockwise rotation ,mostly big reel and some counter clockwise rotation (smaller reel ) When did Mitchell change design . Is The original 300 have clockwise rotation ?
Backasswards rotation is one of reasons why I always disliked, and refused to fish with, a Mitchell 300. 😖 🤯
I don't use Mitchell reel for very long time . Last year I bought a Mitchell 408 and a old Fenwick rod ,try to get my brother get back in fishing ,this combo is his favorite . Just putting line for this reel and notice the rotation just like other reel . check out the other Mitchell so only big reel have backward rotation
My 302 for a right-handed person goes clockwise to reel in the line. Edit: that is if you were facing the clock. The 300 I have goes counterclockwise, when facing the clock. If you open-up either one you can see why; simple planetary gears on the 302 and a bunch of gears in the 300 to make that unique oscillation system work in conjunction with the rotor/pinion gears. People who have had line put on a 300 by a machine in the shop have been known to have their line put on backwards by inexperienced persons.
i think the old French-made 300s always had a rotation different from just about everyone else. Not sure if clockwise or counter--I guess it depends on which way you are looking at the reel. Just the opposite from almost everybody else, though. It has never bothered me.
Frank
Counter clockwise rotation will bring the line to the pad of your righthand index finger so it is easy to grab the line for the next cast. Clockwise rotation will bring the line to the nail side of your index finger making it more difficult to grab the line.
The 300 is the only Mitchell I am aware of that spins backards?
I do remember 300 go backward but the two 300 I have right now have same rotation as any other reel on market today .The 408 ,300A ,300 Pro ,900 ( smaller reel ) all have right direction . Only 302 ,398,306 have backward direction . That why I ask when Mitchell change direction on reel
Pictures; 1) 302, 2)300 and 3) 300 including oscillation unit.
The 302 was my attempt to imitate what a member here did awhile back to strengthen the crank system by stabilizing it with 2 main gears. It does seem stronger like that. Is that member still here? I remember he received the usual excess of criticism for his project, so maybe he bailed.
I messed up , 300 ,300a and 900 go backward . Other have same rotation as other reel
I believe the 330 does also
I don't have 330 so I don't know , Actually reverse rotation have some good point , when casting just extent index finger to stop rotor right at place to pick up the line
Quote from: Gfish on November 10, 2025, 04:13:33 PMIf you open-up either one you can see why; simple planetary gears on the 302 and a bunch of gears in the 300 to make that unique oscillation system work in conjunction with the rotor/pinion gears. /quote]
Are the pinion and drive gears cut differently or at different angles on these models vs. the 308/408 or models that rotate clockwise?
I liked my 300's bc having both a cup rotor and clockwise backward rotation made the 300's the most comfortable to back-reel. Now, if the skirted reels back-reeled clockwise, I'd probably have converted to fishing drag long ago. A sad day that would have been. I'd probably be a different man altogether. :ct
EDIT: I found my memory faulty on the advantage of clockwise back-reel rotation; The bail is also "reversed" of course, which brings it into contact with the rotor feathering/controlling hand of the back-reeler. Not much of an issue with the cup rotor reels as the bail armatures are small.
Quote from: Paul Roberts on November 14, 2025, 08:57:13 PMI liked my 300's bc having both a cup rotor and clockwise backward rotation made the 300's the most comfortable to back-reel. Now, if the skirted reels back-reeled clockwise, I'd probably have converted to fishing drag long ago. A sad day that would have been. I'd probably be a different man altogether. :ct
I remember in Mitchell instruction booklet they recommend only use anti-reverse when fighting fish and most fisherman back-reel because their drag not reliable also cause twisted line
It's true. When using an MG 300 with light line and(or) bigger fast-moving fish like Steelhead, the stock drag may not be able to slip at the right time. A forefinger pressing on the underside if the rotor with the A/R off might work better.
I view back reeling as a recipe for disaster, so the way I see it, if I can't trust the drag on my spinning reel to work correctly every time it's needed then I don't think I can trust the reel. To me, the drag function on a spinning reel is it's overall most important function, and always has been. More fish have been lost because of a malfunctioning drag and/or adjustment than any other aspect of a spinning reel. That's why I only seriously fish ABU branded fulcrum drag spinners.
I was taught, correctly, to play and work fish by using the reel drag system in conjunction with the flexion of the rod one is using.
Well, I've been watching this thread with interest. Tommy just nailed it. I love Mitchell reels. That being said, the combination of the drag and the rod action make up the major portion of fighting a fish. Of course, that's my opinion. Everything taken in consideration together, reel, rod, line and knots, they all work together. But the drag,,, so important in the chain. Back reeling, I save that for letting line out to secure the lure to the rod at the end of the day!
Quote from: quang tran on November 16, 2025, 03:46:39 AMI remember in Mitchell instruction booklet they recommend only use anti-reverse when fighting fish and most fisherman back-reel because their drag not reliable also cause twisted line
Hi Quang Tran. It doesn't appear that the Mitchell booklet has anything to say about back-reeling. It refers to reeling while drag is outgoing. Here's the quote from my ~1964 Mitchell 300 manual:
"Set the anti-reverse the instant a fish strikes. When a fish is taking line against the drag, do not attempt to slow him down by retrieving. You are accomplishing exactly nothing - and you are putting unnecessary twists in the line."
That said, I did back-reel a few Chinook salmon with a 300, that may have contributed to it sounding like a box of gravel eventually. I attribute this more to the multiple relatively soft metal gears in the 300's (a lot of teeth needing to mesh!). I did not know back then about all the shimming required to keep a 300 from complaining so loudly. I did acquire a DAM Quick 441N for my salmon fishing then, for its' big spool and 5:1 ratio. I could follow their runs without having to leggo the handle! EDIT: However, doing the math on known potential salmonid burst speeds, no reel could keep up. That is, with fresh strong healthy ones in peak water temps. The salmon I caught back then were not the bright chromers. On such fish, esp with appropriate sized reels, back-reeling would be pretty uncomfortable. Great with fish that don't make sustained runs, and require large reels. A large handle and rotor spinning that fast...you'd want to keep your fingers away til it slows down. But, for freshwater fish, esp any warmwater species, back-reeling has more advantages than disavantages.
My reference to 300's being nice to back-reel -and other older spinners- is due to the cup type rotor. I actually just picked up a 300 yesterday at an antique shop, 1964 NIB. And I found my memory was faulty on the advantage of clockwise back-reel rotation; The bail is also "reversed" of course which brings it into contact with the rotor feathering/controlling hand of the back-reeler. Not much of an issue with the cup rotor reels as the bail armatures are small. But a skirted reel with those big wings sticking up spinning in the wrong direction -toward the fingers rather than away- would be a problem for back-reelers.
Well... I long ago stopped trying to convert anyone to back-reeling. I know it sounds...scary. But it's not. In response to the naysayers, who've almost certainly never tried back-reeling nor learned it proper, I will say this: Back-reeling is easy, is not risky, and simply gives much better -no complete- control of fish. Giving line to a fish prematurely is what puts a catch at risk. I simply can't abide letting the fish, or a mindless stack of washers, dictate the fight. I've seen enough of, even bass pros, fumbling with drag mid-fight, or yanking line off reels at boatside. Ridiculous.
Drag is a crutch that no one dares to leggo of. I can say from decades of experience, that it is unnecessary -at least for FW fishes of all types and sizes. An exception might be big (15+) fresh chrome steelhead in 50F water with room to run. Not that back-reeling wouldn't work but drag would just make things easier on those longer runs. However, I've back-reeled plenty of Great Lakes rainbow/steelhead, even Chinooks, on spinning gear and never had an ounce of trouble. I can't speak to gigantic long running SW fishes. Some of those brutes might be a bit too much for any person or reel! If I ever get that chance, I'll let the mindless stack of washers do the work.
Hi Paul , Mitchell don't say anything about back-reeling in their booklet but they do recommend only use anti-reverse when fighting fish . I start fishing with Mitchell reel and I do have lots of problem with their drag , may be from lack of knowledge and reel maintenance . I never back-reeling but I do tight it up on some reel that gave me problem ,later I switch to DQ and Daiwa and retire all Mitchell reel
You mention that the drag on Michell are louder and i like that point , Just like someone replace car muffler with they call high performant muffler . I going to use some small Mitchell reel for crappie in winter this year , sound so sweet in middle of night
I've found that letting a big runner do its thing while maintaining light finger pressure on an old-school round rotor is good for tiring the fish-out. Also if drift-fishing a river you can extend the drift by the same back-reeling method.
Quang Tran, I was referring to the gears being noisy on the 300's. As to the drag...I've never heard one! :)
Gfish, I've not SW fished with spinning tackle (I've been a fly guy there and caught many stripers, blues, and some albies on single action reels. Some cool advantages there too!) And, yes, there are lots of advantages to having the AR off with spinning tackle; At all times -except when keeping the lure on the rod's hook keeper -the only time I use AR. What else is it good for I always wondered? ;D
For those curious at all, two hands are at play when back-reeling:
-The crank hand, as most fish and runs can be handled with rod length and maybe a few turns of the crank, if even needed.
-And the rod hand which, as Gfish is talking about, keeps the rotor in check. If a fish is fast enough, either in a burst or a full on run, the crank hand can 'leggo the handle'. The reel easily gives line. When the fish slows, turns, or stops, the rod hand fingers are feathering the rotor, or I can simply clamp down on it. Then the crank hand is back on the job.
Skirted reels do have 'wings' that could be trouble, but only if the rotor spun clockwise. Or perhaps on really big reels, but I'm talking FW here. I do realize that, for left-handed fishers, feathering a skirted rotor would not work as well. The rotor wings would be spinning in toward the fingers, instead of away. Less an issue with cup rotors though. In fact, I realize I did this myself, as a righty, with my Mitchell 300's and their "backwards" rotor motion. You know, I back-reeled a few Chinook's to 24lbs with that trusty...box of gravel. :)
One big advantage to back-reeling chinooks from terra firma (pier fishing) was not having any line twist build up over the course of a fight. I remember a buddy's long fight with a 26lber, using drag, and his line was so twisted by the end it was unusable. Protocol became having a spare spool or reel along just to deal with this issue. I don't know to this day if drag itself, over many revolutions, builds up twist. Or if the guys were inadvertently reeling against drag some during the long fights?
The biggest advantage is how fish fight when line tension is under precise real time control, vs having a drag slipping and letting a fish turn its head away from you. The head has to be pointing in your direction to bring em to hand. Otherwise you may have a prolonged battle with teh fish's considerable body and fin area. Want more fight when back-reeling, lower the rod a bit to release a bit of tension and let the fish bite into the water again -yee-ha! Otherwise, you really want that fish, don't want it wrapping up in weeds or wood, stalemating you in current, getting far away and affecting a fixed drag setting, on a short line at boatside, etc. Catching fish is all about controlling line tension. And back-reeling gives you that control, from the cast, through the nuances of presentation, strike detection, fighting, and landing.
I'm not the only back-reeler remaining either. We just don't tend to talk about it. Those that haven't used it couldn't possibly understand: https://www.outdoorcanada.ca/backreel-and-thumb/
Well, I guess I haven't totally given up on trying to convince folks that BR-ing isn't just for old reels with poor drags. It's its own world.
Boo-hiss I say of the new reels with no selective AR, only provided a clutch crutch! Save the clutch for... billfish and tuna?
When casting and retrieving with a spinner, the line is twisted as it is wound on the spool and then untwists when cast off the spool. When line is pulled off under drag, it does not untwist the way it does with a cast. So, a back and forth tug of war adds more twist every time the handle is turned.
We don't tend to notice small amounts of twist, except perhaps with certain fluorocarbon lines >:( . But fishing certain lures (spoons, spinners), and accumulated drag use, can wreak havoc. Of course there's an easy fix, clip off the lure and hang the line in the water. Easy in a boat, not always easy along some shorelines.
Letting a big'n run with the reel A/R off and fingering the rotor is part of a finesse system that gets me, it seems, more strikes. It was thought to me by my ladies father, mostly fishing big trout in lakes. Maybe some guy adopted it for spinning reels by watching Fly fishermen palm the rim of their reels.
My Steelhead/Salmon rig was a 9' Fenwick, with a good lower backbone and a sensitive tip, with the MG 300 and 10 lb. test line. Most places I fished were kinda crowded and most guys had long rods like mine but thicker and stiffer baitcasters. Ambassadeur's, Penn Levelmatics, and early Shimano's with 12-20 lb. Line were common. This was all bank fishing. From what I've seen though, drift-boat fishing was very best way to score consistently.
I'm not bragging(well, maybe I am...)but I usually got more strikes than others. My rig was lighter, casted further, and I was able to use less lead to get a good drift bounce. A good bounce on the bottom with pencil lead was a must to me. I could cast for a longer time than most others and it seemed, have better control over my terminal tackle.
But..., it wasn't easy to fish around me when I hooked-up. Finesse means more time hogging the bank as you carefully play the fish on light line and let 'em run up or down the river. Guys would get pissed, waiting for me to land 'em. But I was young and self-absorbed and good at not paying them any attention. Plus there was my ego to massage. I have to admit, my SOB self used to get a kick out of those guys shouting advice at me while their fish-less selves stood by and could only watch.
Quote from: oc1 on November 17, 2025, 06:31:31 PMWhen casting and retrieving with a spinner, the line is twisted as it is wound on the spool and then untwists when cast off the spool. When line is pulled off under drag, it does not untwist the way it does with a cast. So, a back and forth tug of war adds more twist every time the handle is turned.
Thanks, Steve. Which makes me wonder, there are those revolving line winders one can get for spinning reels. If they manage to put the line on a spool untwisted, say the way a tackle shop line winder does, the first cast would create twist. The retrieve might untwist? Unless the lure is stationary -not allowing the twisting/untwisting of the line on...cast or retrieve... Do I have this right? I think I'd have to see this empirically, can't quite visualize it. This is a thread topic all itself. Apologies to the OP, Quang Tran.
Personally, I use ball bearing swivels. Do they eliminate all line twist,,,, no. Do they eliminate some,,, yes. Do they affect the action of the lure,,, fish are not that smart in my opinion. All my opinion.
Quote from: Reeltyme on November 28, 2025, 11:15:54 PMPersonally, I use ball bearing swivels. Do they eliminate all line twist,,,, no. Do they eliminate some,,, yes. Do they affect the action of the lure,,, fish are not that smart in my opinion. All my opinion.
That's the twist from lure as spoon and inline spinner ,we get these twist even on bait casting reel ,swivel eliminate these twist but won't help the twist from spinning reel .Swivel do effect the action of some bait suck as Rapala
While we're veering off on many courses here (good stuff I think), and quang tran is OK with it...
I use a ball-bearing swivel with spoons, also with large spinners when using a wire leader. With smaller spinners I tie direct. One thing I do to reduce twist with spinners is to bend the line tie wire at about a 40-45deg angle, keeping the line tie loop horizontal which allows it to plane a bit. Together these help keep the lure from rolling over. It still collects some twist and I will snip, release the twist, and re-tie every now and again while I fish. The Mepps #3 Aglia is a favorite, and virtually forgotten, bass lure. Retrieved straight in with speed and direction changes. That and the #2 are great in very clear wintertime waters too, yo-yo'd like a blade bait. They take it on its sliding gliding somewhat erratic fall.
Since I moved to Houston ,TX I very seldom use inline spinner ,they don't seem to work good here ,only work for white bass but I prefer to use jig for them as it easy to fish close to bottom and it's cheap to loose some . Large mouth prefer plastic worm ,spinner bait or bass jig . They are stocking some small lake here with rainbow trout ,spinner work good but i don't find much fun to fish for them .I still have lots of Bluefox and rooster tail unused
Yes, spinners are getting expensive, and they are snag risky, esp around wood. There's some ways around that -the snag potential- but it's true they aren't cheap. Try a larger Mepps Aglia. They work well in open clear water, move a lot of water yet give off few bad cues. If they work in NY, PA, and CO, where I've fished them, they'll work in TX. Lotsa good lures, so little time though.
Quote from: Paul Roberts on November 28, 2025, 05:51:07 PMThanks, Steve. Which makes me wonder, there are those revolving line winders one can get for spinning reels. If they manage to put the line on a spool untwisted, say the way a tackle shop line winder does, the first cast would create twist. The retrieve might untwist? Unless the lure is stationary -not allowing the twisting/untwisting of the line on...cast or retrieve... Do I have this right? I think I'd have to see this empirically, can't quite visualize it. This is a thread topic all itself. Apologies to the OP, Quang Tran.
That's right Paul. But there are two other ways to load line on a spinner. (#1) You can put the spool of line on an arbor and let it rotate as you load it on the spinner. Or, (#2) you can lay the spool of line on a flat surface and let it uncoil as you crank the spinner. If you set the spool of line down in the correct orientation (label up or label down) then each coil that comes off the spool of line will counteract one twist being imparted by the reel rotor. This helps a little. But the trouble is the spool of line is usually a much larger diameter and circumference than the reel spool. So, the reel's rotor rotation puts several twists in the line for each twist being counteracted by the coils coming off the larger spool of line.
But, regardless of how the line is initially loaded, the important thing is that the reel imparts twists when casting but removed twists at the same rate when retrieving. So, twist does not build up and become a problem if the drag is never used and the lure doesn't spin. A certain amount of twist is, thus, inevitable but it does not really become a problem if the line doesn't coil up on itself a lot when there is some slack line.
To help visualize it, take a piece of ribbon and pretend you are going through the various permutations.
Something I learned many, many, years ago was to never turn the handle when a fish is taking out line against the drag. I don't seem to notice too much excessive line twist if line is just being pulled out, but trying reel against line being pulled out really exacerbates line twist and excessive looping. I exclusively use 6# & 8# mono so I regularly hook my lure/line to a tree and stretch the first 50 or 60 yds since it's so easy.
Yeah, but Tommy, you get the same twist build-up effect in a back-and-forth battle where the fish pulls line out against the drag and then that line is wound back on with the rotor.
That's the twist from lure as spoon and inline spinner ,we get these twist even on bait casting reel ,swivel eliminate these twist but won't help the twist from spinning reel .Swivel do effect the action of some bait suck as Rapala
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I don't really agree with your point that the swivel only applies to the lure twist and not the line. The swivel allows the line to spin as the lure remains in its designed position. As you reel and the amount of line left past the end of the rod gets shorter, the amount of twist in the line increases. The swivel will allow the line to "untwist" to some degree. It's like holding a rope that's tied at the other end and twisting it. At some point the twist starts to double over on itself and knot. Add a swivel to the tied end and again try twisting the rope. Again, like I said before, the swivels do affect the action of a lot of lures I just don't think that a fish that can be tricked into biting just about anything you throw in the water is smart enough to decide if a lure is acting correctly. Just my humble opinion!
I always have about 20" of leader between a lure and the main line. And every lure gets a ring on the front. About a minimum of 4' between slow trolled bait and the swivel. Best is a ball bearing swivel, but the line will still twist some. The down-side is 2 extra knots at the swivel.
Quote from: oc1 on November 29, 2025, 04:46:01 AM...
But, regardless of how the line is initially loaded, the important thing is that the reel imparts twists when casting but removed twists at the same rate when retrieving. So, twist does not build up and become a problem if the drag is never used and the lure doesn't spin. A certain amount of twist is, thus, inevitable but it does not really become a problem if the line doesn't coil up on itself a lot when there is some slack line.
To help visualize it, take a piece of ribbon and pretend you are going through the various permutations.
Excellent description, Steve!
Tom, yes reeling while drag is outgoing is the fastest way to put excessive twist in line. But twist does build up over time, with every pull on the drag. It may take some time to build up, except with large long running fish it becomes painfully noticeable, esp with fluorocarbon, less with braids.
Ball bearing swivels help some, anywhere on the line. Some lures, and rigs, can be line twisters. And loading line onto reels, even when done "correctly" adds some twist.
My fix, for all of the above -besides back-reeling- is to get ahead of the inevitable accumulation, by hanging a free line in the water behind the boat, walking a shoreline, or hanging in stream current. As a back-reeler I don't have to do this very often, unless I'm using lures that twist line. I then may hang my line every few hours. Well worth the small interruption in the fishing. Twisted fishing lines can be a horror! A scientist friend of mine (not a fisherman) was coiling up some string and commented on how complex the physics of the forces operating on "strings" is. I responded that every fisherman has some understanding of that.
Ever had an "episode"? An EPISODE!!! (proper spelling) is when you get a minor tangle. You go to quickly untangle it, and it gets worse. It wraps on a guide, catches a button on your coat sleeve, then a weed end, then a twig, then an entire F'ing oak tree! If you don't STOP right there it'll be wrapped around your neck so tight you'll be found beheaded! THAT IS AN EPISODE!!! I've come to realize when one is brewing. I then STOP, sit down (literally), and breath...Oooowwwwwwmmmmmmm... for several long relaxing minutes. And remarkably, the tangle unwinds itself!! "What the hell was that?" I always wondered. I now know: It was an "episode".
I always wanted to see a video of myself when one occurs, although I know what I will see. I'm moving too fast and causing it myself. I know it appears that there is some cosmic force or some mysterious physics going on. But no, I am the source of those mysterious forces, only egged on by an errant breeze; you know, the kind that can emanate from a butterflies wing.
That's ok with me, getting excited when the bite is on and making mistakes. I still have that little-kid aspect to my fishing.
A great challenge for me is fishing at night and keeping my headlight off as much as possible.
G, for me it can happen anytime. Sometimes it happens away from water! :-\
The twist getting more serious on light line ,more problem on Mitchell reel than other reel and I fish at night quite often .
My fix is simple , Using shallow spool and change line more often with 4 lbs test and 6 lbs test ,sometime every trip . Shallow spool don't hold much line and I have enough to fish for the rest of my live . Also I used to carry an extra spool
Here's an idea!
When I get line twist ,I use this set up . It is 3 barrel swivels on a string tied to the post in front of the house . I put on another barrel swivel with a clip on the leader to hook to the 3 inline . Walk off 50-75 yards than flip the bail and start reeling under pressure . Stop every 25-30 cranks and relaxed the line so the barrel swivels do their thing . This usually gets me through a day of fishing . Wash , rinse and repeat at the end of the day .
Is it work like back- reeling ? I think Ryobi made one similar long ago
That's pretty cool Joe. Interesting it takes 3 swivels to do the job. Might work better if they are spritzed with thin reel oil? I wonder if a large ball-bearing swivel would be even better. And it never occurred to me to oil a BB swivel. I wonder if a PTFE oil -that is supposed to bond to metal- would remain tenacious enough in use underwater? 💡
quang tran, yes same effect, with line going on and off spool the same. The reel pictured seems like an odd contraption to me, but if the rotor bearing is smooth and well balanced it may not feel too strange! And you wouldn't have to ever let go of the spinning handle when back-reeling -not that that happens all that often. I do question how robust the mechanism (dog?) might be that releases and re-engages the rotor from the drive train. Might be adding some complexity there that... a simple AR switch doesn't already cover.
The "CAN'T TWIST". What a stupid name for a reel. I'll bet I can get it to twist, just do some trolling or cast a spin-lure with a tweaked shaft.
If I feel the need to use a swivel, usually only when trolling, I use barrel swivels exclusively, not because I think they're the best, but because I'm a tight arse, they're cheap and quite a bit more compact than ballbearing swivels. There's really no comparison between the quality of the two. If I'm going after something tough like Northerns or Muskies I'll use a ballbearing swivel, otherwise, for mainly walleye trolling, I use the smallest black barrel swivel I have.
On a little different note, I bought a can of Dupont Multi-purpose Teflon spray lubricant when it first came out thinking it would be a God Send. I hate that stuff! It seems to gum up everything I've ever sprayed it on with some whitish gooey crap.
Good quality barrel swivel like AFW is all I need . Work better than Chinese ball bearing swivel. for heavy duty deep sea fishing then we may need Sambo swivel
I've previously wondered if fish oil (the supplement) applied with a needle might be great lube for swivels with a smell that might not scare away the fish.
...buttt then Gary says spray your lure with wd40 if you want more hits. Haven't tried it. But it threw the above into question.
Also, the no-twist design clearly didn't catch on.
Quote from: quang tran on December 03, 2025, 06:58:00 PMGood quality barrel swivel like AFW is all I need . Work better than Chinese ball bearing swivel. for heavy duty deep sea fishing then we may need Sambo swivel
That's good to know.
Quote from: JasonGotaProblem on December 03, 2025, 08:29:00 PMI've previously wondered if fish oil (the supplement) applied with a needle might be great lube for swivels with a smell that might not scare away the fish.
...buttt then Gary says spray your lure with wd40 if you want more hits. Haven't tried it. But it threw the above into question.
Also, the no-twist design clearly didn't catch on.
There is a rather in-depth chapter in Keith Jones' book "Knowing Bass" about chemoreception (smell and taste) research on LMB and some other fish. He mentions a number of things that bass either hate or simply cannot sense. Among the former are DEET, soaps/detergents, and sunscreens with PABA, nicotine (to minnows anyway). Among the latter: Anything non-soluable in water such as oils; "Neither gas nor oil, for example, is noticeably repulsive to bass. We have offered bass food dipped in straight oil, only to watch them eat the coated morel with no apparent reluctance or side effects. However, various petroleum additives -detergents for example- can transform oil products and make them offensive."
WD40? I'm pretty skeptical about such claims though. Mostly bc of the sheer number of variables involved in a natural environment, esp mixed into our fishing trips. Trying to tease such a singular thing out would require some serious effort most anglers would never do, much less have the controls in place to really be able to say something. Often a few positives is all it can take to convince ourselves of something. Been there, done that. And...will do it again I'm sure.