shouldberiding

So I'm in a bit of a pickle. I need a new freehub body as the current not only is slipping but actually locked "open" on me once forcing me to walk the last 2 miles of a commute. But...

According to my research, the hubs on my bicycle wheels are of a defunct design from the 1990's. Seeing as how this bike was brand new six months ago, I found that a bit odd. It's an 08' Trek 7.3FX.

It's a Shimano Parallax FH-RM60-8S-QR rear hub. I've found the part number for the freehub body (Y-3CF 98040), but I'm having no luck searching under that part number. Everybody is out of stock. I'd be fine with ordering a whole hub with a compatable freehub body and using it for parts.

Anybody know if another Shimano rear hub would have the same type of freehub body on it? It's not compatible with current Shimano offerings as the splines are on the freehub body rather than on the hub. If I'm not using the correct terminology, the teeth are on the bottom of the freehub body rather than on the hub.

TallRider

I'm pretty sure that Shimano freehubs from the early 1990's are compatible with today's freehubs - there were differences in attachment (uniglide-compatible freehubs) but the freehub bodies will still attach onto the hub shell the same way. You probably have a 8/9/10-speed-compatible freehub as it's a recent bike.

All freehubs have the spline on the freehub body, not on the hub shell.

Can you take a picture and show how your hub is weird, if it is?

bikinfool

Time travelling hubs! If you bought the Trek new, and that certainly isn't a stock hub, why don't you go back to the shop you bought it from? If you bought it used, well I guess you can't do that, or don't really have an 08 Trek 7.3FX...or your research is off. Pictures or more details on your research...

shouldberiding

Can't take pictures, but I've got some .pdf docs from Shimano with the exploded view of the hub.

Here's a Deore rear hub:

https://techdocs.shimano.com/media/te...9830608927.pdf

Now, here's the Parallax hub on my wheel:

https://techdocs.shimano.com/media/te...9830608952.pdf

EDIT: Yes, purchased new from a bike shop.
You can't see the back of the freehub body, but it's clear that they attach in a different way and aren't compatible. The "teeth" are visible on the Parallax freehub body with the recieving splines on the hub shell, whereas the Deore hub has the teeth on the hubshell with the recieving splines on the freehub body.

DOS

This https://www.trekbikes.com/us/en/bikes/road/fx/73fx/ indicates that the bike came stock with a Ahimano HG-40 cassette, which are pretty widely available. And waht does "locked open" mean in context of a freehub?

bent-not-broken

If you are riding in Madison this time of year you are probably experiencing free hub freeze. Either the lube is getting thick or you have some moisture in there that is freezing and causing the pawls to not 'ratchet freely'. This is a common winter problem. Flush the hub with WD40 to thin the lube and remove moisure. Follow with a light oil. I doublt the hub has failed.

bikinfool

I find it nearly impossible that a new Trek came with an old Parallax hub, sorry. If you have a weird shop that has strange ideas about parts swapping I suppose it's remotely possible. Did you find the model number on the hub? Should still be under warranty if it's a new bike in any case...

ps looking at the link DOS provided, you should have an RM30 8 speed like this https://techdocs.shimano.com/media/te...9830612964.pdf

ps Okay, got me to thinking, maybe Shimano has revived Parallax again? Is it possible?

WNG

The Parallax terminology was to introduce Shimano's wide hubshell freehubs to MTBs back in the mid 90s. They were 7, then 8 spd freehubs. These days, just about all their hubs are wide-bodied.

The odd thing is the changeover in design of the interface. I have an old 90s Parallax wheel somewhere. I believe it's the standard Shimano spline interface. As well as an FH-RM40-8S freehub that is standard spline.

If this is a new bike, then the freehub must be current stock. There is the possibility the design is for OEM parts, or another attempt by Shimano to file more patents on their freehubs.

I'm sure the freehub body is available. And your LBS should be able to order it.
But I tend to agree with others, that your freehub body probably needs to be flushed and filled with proper oil compatible with your riding temperatures.

shouldberiding

The rear hub indicates that it is the FH-RM60, not the FH-RM30. Possibly a change for the '09 version. Anyways.

They list the Y-3CE 98040 freehub body for the RM30, and the Y-3CF 98040 freehub body for the RM60 that I have. I've no idea what the difference is.

I did have a mechanic thoroughly clean and re-lube the freehub body and I'll be able to test it tonight to see if it's better. I'd already flushed with WD-40 and that did free up the pawls, but I was still experiencing the occasional slip.

If I experience any more slipping I'll be heading down to the bike shop where I bought it. It seems really weird that Shimano would have two different hub interfaces.

Thanks for all the help, folks.

I_bRAD

Why don't you just take the freehub to your LBS and they can match it up for you? Shouldn't be too hard to find a replacement.

bikinfool

My mind was stuck on the Parallax phrase...which to me was a different type of drive somewhat, a silent one at that (great stealth hubs is what I actually remember)...are these silent when coasting?

Is it your shop that can't find the replacement freehub or are you trying to source it on your own rather than have it done under warranty?

Panthers007

I bought an '08 FX 7.5. The freehub is current, but the chain was so stretched it was making lovely 'clicks' with any weight on the cranks. I took it back to the shop I got it from. They admitted there was no way this could have happened between sales date and the present. They said they'd been seeing this quite a bit lately - as they put on a new SRAM to replace the stretched Shimano.

My guess: Trek had run out of chains and put on an old one they had kicking around. Perhaps this explains your antique freehub? What does their warranty have to say about weird, defective, old original equipment?

shouldberiding

The original plan was to get the tools and do the job myself. Sounded like a good idea at the time. It was pouring freezing rain out and this LBS I went to was 3/4 mi closer than the one I purchased the bike from. Guy on the phone convinced me just to bring the bike in to have them fix it. I was a little out of my mind at that point and just wanted my bike fixed. The mechanic there hadn't seen a freehub body like that before and doubted I could even find one, offered to sell me a new rear wheel. I...passed on that offer.

Yeah, the slipping was even worse tonight so I didn't even bother going home. Instead I went straight to the bike shop I bought it from.

Not only did the mechanic know what kind of freehub body it was, they had one in stock. Of course did the job under warranty.

While he was putting the bearings back in place he turned to me and asked, "When you had the hub apart, did you drop a couple of bearings in the hub?"

Wha?!

I've learned my lesson. Props to Machinery Row for having staff who know their ****. Maybe it's placebo, but it felt like a new bike on the ride home! Once again thanks for your input guys.

EDIT: Mechanic at Machinery Row (Dave) even complimented me on the condition of my bike considering the time of year. At least I'm doing SOMETHING right.

Panthers007

Maybe ****er down at the other shop gave you some new bb's?

blamp28

I would be curious as to how a early 90s wheel ended up on your 2008 bike. Was Trek using old parts? Was the bike shop cannibalising new bikes? That's just a bit weird. Glad it's fixed.

shouldberiding

No, stock hubs for that model year. They are current production but info about them is scarce. The mechanic checked three different reference manuals and couldn't even find a model number for it, so thankfully the did have one in stock. All I can find about them is that "Parallax" features a larger diameter hub body. It seems in the Parallax range there are mountain bike models as well as road models. At least, that's what I'm getting from the M and RM designators in the model names.

bikinfool

All I remember about the Parallax hubs (and for mountain bikes) was the silent clutch drive. Now that I do some looking around, apparently they just happened to be offered with the new at the time fatter hub bodies that are fairly normal with Shimano mountain bike hubs now. Always thought they were one and the same for some reason. Hope your hub doesn't actually have that silent clutch freehub, they were problematic from what I remember like in this thread https://www.bikeforums.net/archive/in...p/t-77856.html

zsjoske

For future reference, as i also had the exact same problem. There is a solution. With thanks to Paul for his post on https://www.singletrackworld.com/foru...s-freehub-body

The freewheel body for the RM30 (i think partnmr is Y-3CE 98040 but not shure..) is almost identical. And widely available. And cheap. I just replaced mine and it works just fine.

edis

There are still some freehubs in this form factor, I would say RM33 should be official late replacement for the original RM30 freehub (including Parallax RM60 variety).
Applying WD40 or light oil can free thingie momentarily, but there must be two kinds of thick and thin oilings inside, therefore most likely will ruin the part. In fact, I've heard saying, that thick oil creeping, where light oil is supposed to be, does cause more delicate part to stick, bringing whole unit down.

Freehub is awkward to open, needs specific tool, yet easy to exchange with the replacement one.

mack_turtle

you bumped a thread from 2009 as your first post.

edis

Sure. As it was on my way of research, information in there still will be useful much longer, than the timeframe of the initial chat. Some forums lock their threads, and you are out from adding good stuff - that's wrong to do.

I even bothered to register for the site to offload my share of accumulated knowledge here. It's fine, if tolerated by policies.

HillRider

Bringing back a zombie thread is common on this forum so no problem.

As to lubing freehub bodies with light oil, it does work fine and can free up sticky pawls and make the freehub work properly. I've never heard that any freehub body has or requires two kinds of oil. Thick oil (or worse, grease) can can lock the pawls, particularly in cold weather. I've always re-lubed Shimano freehub bodies with Tri-Flow by removing the inner rubber seal and flushing it thoroughly with Tri-Flow, draining the excess and replacing the seal. I have a couple of freehub bodies with over 50,000 miles in perfect operating condition and that's the only lube they have ever seen.

edis

Hi! Thick oil goes to the base, where joint to the shell works his work. Light oil to the pawls, correct. I wonder what they did to the RM33 to revise construction. Found quite some evidence RM30 is poorly designed (low feedbacks). On many of my bikes, this freehub is the first that bugs me.

dmark 

https://si.shimano.com/pdfs/ev/EV-FH-RM60-8S-2391A.pdf is this what you have? (teeth on freehub facing outward)

edis

Yes, this freehub ends with, and is recognizable by, exactly kind of small sprocket/teeth. RM60 is clearly one of the hubs it goes into. Other end of purposes - to serve HyperGlide cassettes, usually HG30-50 and derivations, I'd say. TX800 hub is mentioned too, as an exotic offspring.
BTW, I reconsidered, that what I call thick oiling/lube might be known as grease at your end. Quite expected elsewhere in the hub, therefore no surprise load handling end would be smeared with. Sticking pawls is where it is not at all welcome.