masi61

I am building up a used Masi Gran Criterium with some clean used Shimano Ultegra and Dura Ace parts. The integrated shift levers are clean used Dura Ace 7800 rear and 7803 triple front. They have minimal scratches although I did replace the hoods at one point though I have never finished this build. Now I am moving forward again on the build and find that the front shifter has no clicks in either the upshift swing or downshift swing.

I was going to spray some PB blaster into the internals to see if anything gets freed up as I sweep the shifter through the upshift and downshift modes.

I'm curious if anyone has successfully used PB Blaster spray for this application. I thought there were stronger solvents in it compared to WD40. I don't want to damage any delicate mechanisms but I do want to break up dried grease if this is the issue. Thanks for any help.

KerryIrons

You don't need "stronger" solvents. If the shifter is going to be revived by a solvent flush, WD-40 will work just fine at getting the gunk out. Flood the thing while shifting through the gears. If that doesn't work, then the shifter is likely shot.

andrewclaus

I reserve the PB Blaster use for the severely frozen pawl. Once in a while you need to dismantle the shifter and get a dental pick on one of the pawls to work it free. If that doesn't work right away, a drop of penetrating oil helps. I don't know if penetrating oil is as good a cleaner as WD-40, which I hear is largely kerosene. And flushing out a shifter is the only place on a bike I use it.

Dan Burkhart 

WD 40 almost always works for me, and when it doesn't it's because something else is going on besides gummed up works. I do find that it sometimes takes patience though. Sometimes it takes hours or even days to thoroughly dissolve the gunk but that is usually in a shifter that has not been used in years. Otherwise, results are more immediate.

Andrew R Stewart 

The goal is to remove the old gummy lube, not just dilute it. Solvents and penetrating oils are poor lube, although they usually work well for the dissolving the old they are poor lubes and really will want a follow up with a true lube (which WD40 isn't). Andy

TiHabanero

About 10 months ago I used PB Blaster on some 105 9 speed shifters and lubed with Dumonde Tech Lite. To this day they still work like new. I use mineral oil mixed with ATF on mountain bike shifters and it works really well if I flush with Clean Streak first. There really is nothing that can get damaged by solvents inside the brifters that I am aware of. Once cleaned out a light lube such as Dumonde Tech Lite works well and keeps the parts working freely.

billnuke1 

Like the wife use to say, “Take that stuff outside!” And I was in the garage!

Andrew R Stewart 

On Shimano's mid 1990s STI versions there's a plastic ring that closes the gap between the two "halves" the covers otherwise have. This molded and specifically shaped band can swell and no longer fit if left in some industrial solvents. Learned this the hard way, but the levers work w/o this sealing band for a while Andy

icemilkcoffee 

Another way to free up gunked up brifters is warmth. Either from setting the brifters in the sun or with a heat gun. Once the brifters frees up you can douse it with wd40 and then lube with Finishline dry lube

cyccommute 

WD40 and PB Blaster are similar in composition. They both contain about 75% mineral spirits (aka “Stoddard solvent”). They both contain a mineral oil. PB Blaster has a surfactant which may aid in penetration of the iron oxide (aka “rust”) structure which enhances its ability to free up rusted parts. It doesn’t contain anything that actually removes the rust contrary to information you’ll find on line.

If you have both, I’d use the WD-40 mostly because it smells better. Both have a fragrance added but PB Blaster’s fragrance is rather unpleasant in my opinion. If you only have PB Blaster, it will work just as well. If you only have WD-40, I wouldn’t run out and buy PB Blaster for this purpose. Neither will really work significantly better than the other.

cyccommute 

I would disagree. The goal isn’t to remove the old lube because it is very difficult to put lubricant back into the shifter without disassembly which Shimano has made very difficult. The goal is to “refresh” the old grease which was likely a soap based lubricant rather than the newer synthetic lubricants that don’t break down as easily. Newer shifters don’t suffer from the “gummy grease” problem at nearly the rate as the older shifters did probably because of a change in the grease being used.

Any spray lubricant is going to contain solvents. That’s the only way that the lubricant can be “sprayed” into place. WD-40 really isn’t any different from any other spray lubricant you care to name. The factory lubricant on shifters is a paste or semisolid lubricant that was physically placed on the part. Any spray lubricant…including WD-40…is going to be inferior to that kind of lubrication because the solvent is used to penetrate and the hope is that enough of the lubricant will be left behind.

WD-40 does have an advantage over just straight up spray degreasers in that they don’t leave any lubricant behind. At least some lubrication is left with WD-40 (or PB Blaster)

Andrew R Stewart 

Stuart's comments are not wrong, I don't disagree with the facts but I do with relying only on a spray as a lube. I think many here seek the quick way out of their service jobs and not always the better results. A solvent will loosen up, mix with and "freshen up" the old stuff. A spray lube with its partial solvent/carrier will do much the same, perhaps take longer to work its way inside the pawls then only a solvent does. But the solvent will in time evaporate away and if a spray lube was used its lube will remain, until that lube dries out too. All this will get the levers working in, usually, a fairly short amount of time and effort AND IF the lube was replenished periodically (as Shimano service suggests it should be, but few ever really do) this light weight lube (spray) should be fine.

My method is quite a bit more involved. At the shops I've worked in we prided ourselves for doing better work that lasts longer than what a home wrench usually can attain. For reviving gummy lube stuck STI (road or MtB) shifters we soaked the shifter core in solvent until the shifter cycled through its range freely. We'd blast out the solvent (and what old lube that dissolved in it) with compressed air. Sometimes on really stuck pawls we'd have to work the pawl with a pick to further allow solvent to get inside its pivot. Sometimes we'd repeat the soak and blast a few times, if the service writer was paying attention they would have done a quicky spray of the assembled on bike lever with a penetrating lube, it would start the softening up process the day+ before the shifter removal and flushing was started in earnest. Once the lever cycles freely and is dry of solvent we spray Triflow in the lever, cycle the lever repeatedly and blast with air to further help the Triflow get into the nooks and crannies. Repeat a couple of times then apply a medium weight drip oil with cycling and blasting a couple of times. If the lever's internals/core was not open I finish with a dripping in of Phil's oil with a blasting then a second dripping of Phil's. letting the levers drain off on a paper towel. If the internals/core was assessable I coat them with a thin film of grease (usually Phil's or Park). Before reassembling onto the bike I do a final lever cycling to confirm all is right. Generally the shift cable inner gets replaced.

This is a lot more effort than most any home wrench does, or claims here and in other forums that they do. But we don't see the levers coming back in 6 months or a year with a repeat of the stickies. We have done many STI flush and lubes that were tried by the rider after reading on line what to do. Either they didn't get the lever to work with simple spray lubes or the problem returned too soon.

Often there's good enough for now repairs and there's good for a long time ones. Often they don't overlap much but as long as the bike works again I guess it's all OK... Andy

shoota 

Tri Flow is my go to for brifters.

bargainguy

I use CRC PowerLube in the red can. Contains PTFE so lays down a little lubricant in addition to the solvent. Never failed to free a gummed brifter with it.

masi61

Thanks for all the expertise folks. I hope to just try WD40 on it tomorrow and will report back here with my results. I really hope this shifter is not toast!

KerryIrons

As others have noted, I should have followed up my WD-40 suggestion with needing to chase another actual lube in after you've got things working. Tri-Flow works well in that application.

cyccommute 

What is this thing that people have against WD-40? Go read the material safety data sheets on WD-40 and Triflow. They are essentially the same thing. They use the same solvent mixture and use very similar oil for the lubrication in similar concentrations. The only real difference is that Triflow has amyl acetate in it so that it smells like bananas.

My main point is that if you are going to use either, it doesn’t matter which. If you want to remove all the old grease…not a good idea in my opinion…use a spray solvent that doesn’t contain oil, then use a spray oil. Or, if you want to keep it simple, use either spray lube and leave it at that. Doing multiple steps doesn’t make for better lubrication.

cxwrench

Exactly. WD is oil and solvent just like everything else. I've used it in shifters for years, no issues.

billnuke1 

And use the air pressure lightly!

KerryIrons

In my experience, what is left behind when WD 40 evaporates is not as good a lube as Tri-Flow. That said, there have been plenty of times where I just shot the WD 40 in there, worked the shifter, and off I went.

mechanicmatt

I have had great luck with CRC Electrical Cleaner, someone showed me as a trick 15 years ago to clean out STI's and Rapidfire mechanisms and it works well. Just hose it in there while clicking back and forth. Maybe wear gloves. Gets the gunk out, and then dries up fast. Then I usually spray back, lightly with some sort of very light lube, maybe an hour later while shifting through gears.

Just cause you put up the challenge, I looked at the MSDS of TriFlow and WD40. I am no chemist but the ingredients look somewhat different and %'s look different to me other than petroleum. That said WD-40 is a decent cleaner but tends to leave a film that is excellent at attracting dust in the long term, TriFlow works very similarly but seems to do a better job of lubrication and less dust collection over the long term. All my opinion and I am sure others would say different, but that has been my experience.

cyccommute 

I am a chemist. The ingredients aren’t sufficiently different chemically to make that much of a difference. WD-40 is a crappy “cleaner” because it contains mineral oil that is the “film” that is left behind. TriFlow would be a crappy cleaner for the same reason. But for lubrication, neither one is going to be significantly different enough for one to be more than marginally superior to the other.

dedhed

I like to do the lube part with this.
https://www.1stayd.com/penetrating-g...x13-25-oz-case

or this, depending on what's in my stock.
​​​​​​https://www.northwoodstm.com/lubrica...oof-lubricant/

masi61

Just an update: I went ahead & sprayed the PB blaster in there and worked the lever back & forth until I felt and heard a click. I then sprayed a bit more and continued moving the upshift & downshift levers back and forth. I am delighted to say that this shifter started working perfectly well again!

I guess I now need to put some spray grease in there now.

jonny7

Has anybody tried an ultrasonic cleaner? I guess it would work well with the inner gunk.