Bosch Gen4 Seal Service & Grease up
- Thread starter RustyMTB
- Start date
That’s good to know………
Nice upload, great stuff
Nice upload, great stuff
Ark
Active member
I bought a park tools crank extractor because all the vids say you need one for bosch..
Then I looked at my pedals lol..... oh whyte use self extracting cranks
BTW, What's the tool called that has the blue handle and basically a hook for removing stuff?
Good video apart from the camera work
Then I looked at my pedals lol..... oh whyte use self extracting cranks
BTW, What's the tool called that has the blue handle and basically a hook for removing stuff?
Good video apart from the camera work
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- Thread starter
- #5
It's just a pick tool & yep, camera work a bit of an aftethought, the GoPro on the chesty & stray left hand not the most helpful but hopefully the main stages are clear. It was Pete the @Bearing Man who impressed the importance of this job onto me. I'm forever grateful to him.
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Nice job !
I thought the camera work created an air of suspense and intrigue at times, with the right music and a bit or work on the lighting it would feel a bit Hitchcock..... What's happening behind the arm .... da da darrr ... It's a SEAL , a SEAL ! Where's he lubing ? It's not one of those types of films is it dear ?
RiderOnTheStorm
E*POWAH Master
- Thread starter
- #9
I think you'd judge it each time. The seals themselves are aluminium or steel with rubber covers bonded on to them. They don't wear quickly at all whereas the grease does disperse over time. Can't give a straight answer other than to say my bike has 2k on the clock & I've replaced them once & they're doing fine.
RiderOnTheStorm
E*POWAH Master
Thanks, that's good to know. I'll keep an eye on mine 
and keep greasing away!!
and keep greasing away!!
- Thread starter
- #12
I mention that in the video. The drive side circlip is a different design from the non drive side, on my bike it has bevelled edges which make it awkward to handle. I bought a pair of cheap pliers & ground the tips at an angle to match specifically for the job.
bazxa
Member
bazxa
Member
It's gotta work for me, I have the same green bike!!
Ken
Member
Hi Rusty, thanks for the inspiration/motivation.
Done the non drive side but would appreciate a pic of your modified pliers for use on the non Drive side snap ring. thanks.
- Thread starter
- #17
Sure. They're some cheapy Amazon or Ebay circlip pliers. I've added the drive side circlip so you can see what I'm talking about. The bevelled edges of the circlip itself tends to make the pliers ping off as you exert force on it, whereas on the NDS, the circlip has a v shaped indentation so that your pliers stay in place. It is a poor design.
If you struggle to remove this in one move, I've found an effective technique is to get one side out of its slot & onto the spindle, where it will stay, then go in for a second try. Once you have the circlip out of it's groove, it's just a matter of expanding it sufficiently to pull it off the spindle, taking care not to mar the thread on the spindle that your lock ring relies on.
If you struggle to remove this in one move, I've found an effective technique is to get one side out of its slot & onto the spindle, where it will stay, then go in for a second try. Once you have the circlip out of it's groove, it's just a matter of expanding it sufficiently to pull it off the spindle, taking care not to mar the thread on the spindle that your lock ring relies on.
Ken
Member
Thanks Rusty, Used all the techniques you suggested and both sides now refreshed. The NDS snap ring pinged off at first attempt and I enlisted my hawk eyed wife to find it among the multi crap in the garage. Progress on the DS was halted by the chainring being virtually welded to the shaft. It has done over 5000mls and much levering was needed to free the micro splines.
cheers, Ken.
cheers, Ken.
- Thread starter
- #20
Wouldn't know about Shimano motors. Might be something online somewhere. Otherwise, I did this for a friend last week on a Trek with 1000 miles on the clock & the drive side seal cover had separated from the metal inner, so worth checking regularly imo.
Adding this to my service interval. Thanks for the tip(s) and showing how easy it can be. I’ll definitely keep an extra seal kit close by after I do this service.
Do you happen to know the part # of the seal kit? (or a link). My local Trek dealer can’t seem to find it.
Maybe it was mentioned here.
I've ordered it through my LBS, but here are the details including part# : Bosch Service Kit Protection Ring BDU4xx | Drive Unit Spares for sale
That should be helpful. Thanks
Peaky Rider
E*POWAH Master
I've been inspired by Rusty's video to service my seals, but those advertised on Ebay etc seem to have conventional circlips rather than the snap rings shown in the video.
Is this a sensible upgrade adopted Bosch or am I looking at the wrong part?
Is this a sensible upgrade adopted Bosch or am I looking at the wrong part?
Peaky Rider
E*POWAH Master
This is the advert from one of my local bike shops. The illustration seems to be a generic one used in many ads. I'm guessing Bosch realised their snap rings were pigs to get out so switched to conventional circlips.
Bosch Bearing Protection Ring Service Kit (BDU4XX)
Bosch Bearing Protection Ring Service Kit (BDU4XX) One Colour £26.65
Thanks
PR
- Thread starter
- #28
That looks much easier to live with! And JE James is obviously a wholly reputable retailer, so it looks like maybe all the techs moaned at Bosch until they changed the circlip. In the instructions Bosch provide, they go out of their way to mention you should only use the circlip pliers illustrated in the document & I couldn't ever find any.
Peaky Rider
E*POWAH Master
My Rail has done 2000 miles in the damp Derbyshire Dales so a service kit is on the way and I'll be using a pair of Screwfix circlip pliers.
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