Bosch Gen 4 - How to change the chainring?

[Like a Boss]

Park Tool CCP-44 will work, but there are other options too.

 

[Paul Mac]

Well that's annoying... The crank puller for the Bosch motor is NOT a Park Tool CCP-22.

Anyone know what the correct crank puller reference number is?

(Should have checked... I now have two CCP-22 tools ?‍. I shouldn't have trusted a dumb sales website.)

You sure you need a puller?
I thought the chain ring was just held on by the lock ring.
Undo this and just slide off the chain ring by hand.

 

[GrahamPaul]

You sure you need a puller?
I thought the chain ring was just held on by the lock ring.
Undo this and just slide off the chain ring by hand.

To undo the lock ring, the pedal needs to removed first. I assure you that pedal does not just slide off by itself!

 

[GrahamPaul]

Park Tool CCP-44 will work, but there are other options too.

Thanks. The CCP-44 was the one I should have ordered. It sure beats hitting the crank with a hammer...

Edit: Ordered this

 

[Like a Boss]

Yea, when you don’t have the tool you sit there and think that there must be a way to get those cranks off without the tool. But there isn’t. Except the hammer and that usually doesn’t end well. So easy with the tool.

 

[Paul Mac]

To undo the lock ring, the pedal needs to removed first. I assure you that pedal does not just slide off by itself!

View attachment 31842

Yes I see what you mean now, I've got sram pedal arms which self extract with an Allen key?

 

[Giff]

I never did get an email reply. I called the USA support number and talked to a tech who seemed to be working from home. He said the o-ring is required. I did get a part number for the o-ring, but no other guidance except to go to a dealer. 1270016119 is the part number. I can't tighten the lockring to 25-30 Nm without the o-ring squirming out of place. Very frustrating, and I don't think it is a solid design. Why not just have a steel lockring, a higher torque value, and perhaps use a blue locktite? The alloy lockring generates alloy bits every time it comes on and off. This does not give me confidence that the lockring will stay tight, as many users have already experienced. There is no reason for this to occur during a ride on the trail.

I know this isn't a Gen 4 and I haven''t done it myself (yet!) but I wonder if the O ring isn't seating properly in it's groove ? perhaps stretched or out of shape and that is making it "squirm" ?

 

[FrenchConnection67]

Hey, I am in the middle of upgrading my chainring to something bigger on my bosh performance gen 4 too. Because the tool is different from gen 3 and quite expensive and seems to be on pre-order only, I ended up making my own spider tool for a £5 and uploaded the video on youtube. To unscrew is clockwise. And you need one of them to remove the crank. Ice Toolz crank removal tool

You guys might be finding this useful.

 

[Giff]

Really helpful. Thanks.

 

[Stihldog]

Well that's annoying... The crank puller for the Bosch motor is NOT a Park Tool CCP-22.

Anyone know what the correct crank puller reference number is?

(Should have checked... I now have two CCP-22 tools ?‍. I shouldn't have trusted a dumb sales website.)

You probably know this by now but the crank puller for gen4 is CCP-44. Picking up right now at my LBS.
I may have to order the spider tool; Unior 1671.2/4 .

 

[GrahamPaul]

You probably know this by now but the crank puller for gen4 is CCP-44. Picking up right now at my LBS.
I may have to order the spider tool; Unior 1671.2/4 .

Indeed I do. Although I bought the Powerpull BTL-14 for half the price of the CCP-44. It works fine. As does the Unior spider tool.

Now I just need to find a source of chain rings to suit my Shimano setup.

 

[Like a Boss]

Indeed I do. Although I bought the Powerpull BTL-14 for half the price of the CCP-44. It works fine. As does the Unior spider tool.

Now I just need to find a source of chain rings to suit my Shimano setup.

E13 makes alloy and steel chainrings for Shimano drivetrains on the Bosch motor.

 

[HORSPWR]

What a genius piece of engineering, now you need proprietary tools or a visit to the dealer just to change out a chainring?

 

[GrahamPaul]

What a genius piece of engineering, now you need proprietary tools or a visit to the dealer just to change out a chainring?

Same as you do for changing a rear cassette or a bottom bracket, no?

Tool for every job...

 

[GrahamPaul]

E13 makes alloy and steel chainrings for Shimano drivetrains on the Bosch motor.

The E13 spec shows the Bosch Gen 4 chainrings as aluminium only. The picture doesn't show the 8mm offset from axle to teeth, so I'll get in touch with them to see whether this is just "art work". I don't think aluminium will be sensible, but I've heard nothing back from FSA or Miranda, so it might be Hobson's choice.

 

[Like a Boss]

The E13 spec shows the Bosch Gen 4 chainrings as aluminium only. The picture doesn't show the 8mm offset from axle to teeth, so I'll get in touch with them to see whether this is just "art work". I don't think aluminium will be sensible, but I've heard nothing back from FSA or Miranda, so it might be Hobson's choice.

e*thirteen Bosch Gen 4 52/53 Direct Mount Chainring - Trek Bikes

Enhance your cycling experience with e*thirteen Bosch Gen 4 Steel Direct Mount Chainring. Shop now!

www.trekbikes.com

 

[GrahamPaul]

e*thirteen Bosch Gen 4 52/53 Direct Mount Chainring - Trek Bikes

Enhance your cycling experience with e*thirteen Bosch Gen 4 Steel Direct Mount Chainring. Shop now!

www.trekbikes.com

That's not showing the same fitting as mine, which has a "microspline" type direct mount. The spec says: "Compatible with e*thirteen quick connect direct mount drivetrain systems" which doesn't seem to describe mine which looks more like this:

Rather than this:

See the problem?

 

[Like a Boss]

Yes, I see the problem. If you search around the internet for the part numbers on the Trek page you’ll find various versions of the chainring. The e13 website in USA only shows aluminium, but e13 makes the steel rings for shimano equipped Rails. The trek web page has had errors before with pictures a and specs, but it’s a start. I bought the w13 alloy chainring because that style increases the chainline slightly, and I think the chainring is too close to the chain stays with my setup (9.8 shimano), but I don’t have it on at the moment and I can’t comment on the alloy longevity. The 9.9 Rails have the alloy chainring and some
of those have racked up miles. It might be that the steel rings are OEM only, therefore not listed on the e13 website?

 

[Paul Mac]

Yes, I see the problem. If you search around the internet for the part numbers on the Trek page you’ll find various versions of the chainring. The e13 website in USA only shows aluminium, but e13 makes the steel rings for shimano equipped Rails. The trek web page has had errors before with pictures a and specs, but it’s a start. I bought the w13 alloy chainring because that style increases the chainline slightly, and I think the chainring is too close to the chain stays with my setup (9.8 shimano), but I don’t have it on at the moment and I can’t comment on the alloy longevity. The 9.9 Rails have the alloy chainring and some
of those have racked up miles. It might be that the steel rings are OEM only, therefore not listed on the e13 website?

I think Zammo on this forum is selling a brand new e13 steel chain ring.

 

[Like a Boss]

E*THIRTEEN Chainring e*spec Direct Mount Bosch CX Gen4 | Steel, 32,77 €

E*THIRTEEN chainring e*spec Direct Mount Bosch CX Gen4 | steel The e*spec direct mount chainring for 12-speed Bosch CX Gen4 e-bike drives A revised narrow M

r2-bike.com

 

[GrahamPaul]

E*THIRTEEN Chainring e*spec Direct Mount Bosch CX Gen4 | Steel, 32,77 €

E*THIRTEEN chainring e*spec Direct Mount Bosch CX Gen4 | steel The e*spec direct mount chainring for 12-speed Bosch CX Gen4 e-bike drives A revised narrow M

r2-bike.com

No! That is definitely not that the chainring for my Bosch 2020 Gen 4.

As you had put the link up a couple of times, I thought I had better check properly so I removed the pedals and the spider nut and then eased back the O-ring. It is definitely a microspline fitting. (Sorry about the mess - a freshly waxed chain).

Something which does make me wonder: there do not appear to be any reports of chainrings coming loose on microspline fittings. Trek appear to be using the hexagon style E-13 fitting from your weblinks. My gut feel is that the hexagon fitting would not be as "snug" as the microspline fitting and would be more likely to come loose. (I have horrible memories of pedals on square fit cranks never staying tight).

Has anyone checked to see if their Trek does actually have the E-13 fitting?

 

[Paul Mac]

Don't be put off by that picture, thats not how they come.
As long as its described as a Bosch gen 4 chain ring it will come with the micro spline that fits your bike, i think they just use a generic photo.

 

[GrahamPaul]

Don't be put off by that picture, thats not how they come.
As long as its described as a Bosch gen 4 chain ring it will come with the micro spline that fits your bike, i think they just use a generic photo.

I guess I'd better send them an email. They show other types of chainring for splined fittings, so it's odd that the hexagon fitting is shown for the Bosch Gen 4. What concerns me most is the specification on their website says: "Compatible with e*thirteen quick connect direct mount drivetrain systems" rather than mentioning Bosch. Puzzling.

An email will also give me a chance to ask about the 8mm offset needed for the Focus chain line.

 

[Like a Boss]

E*THIRTEEN Chainring e*spec Direct Mount Bosch CX Gen4 | Steel, 32,77 €

E*THIRTEEN chainring e*spec Direct Mount Bosch CX Gen4 | steel The e*spec direct mount chainring for 12-speed Bosch CX Gen4 e-bike drives A revised narrow M

r2-bike.com

The R2 bike shop in Germany shows a photo of the part on offer, usually on a scale. That ring must be steel because it’s 209 grams. And you

No! That is definitely not that the chainring for my Bosch 2020 Gen 4.

As you had put the link up a couple of times, I thought I had better check properly so I removed the pedals and the spider nut and then eased back the O-ring. It is definitely a microspline fitting. (Sorry about the mess - a freshly waxed chain).

Something which does make me wonder: there do not appear to be any reports of chainrings coming loose on microspline fittings. Trek appear to be using the hexagon style E-13 fitting from your weblinks. My gut feel is that the hexagon fitting would not be as "snug" as the microspline fitting and would be more likely to come loose. (I have horrible memories of pedals on square fit cranks never staying tight).

Has anyone checked to see if their Trek does actually have the E-13 fitting?

View attachment 33431

You have to click on the pictures on that site. The default chainring is the hexagone mount, to the left of it is the the microspline shimano Mount, 34t, like in the photo of your bike. The same is on my bike. I bought the same chainring in alloy only because I didn’t know they made a steel ring like that. The e13 USA website doesn’t have it. The Rail comes with a less expensive OEM chainring version, except the 9.9. A benefit to this exact chainring is that the chainline comes out to 53mm instead of 52mm. Not much, but watch where the chainring ends up in relation to the chain stay...it’s better. More space if a chain slips off. Hey, let me know if that chainring nut tightens properly over the o ring. My o ring bunches up. I don’t know where to get the o ring.

 

[GrahamPaul]

Hey, let me know if that chainring nut tightens properly over the o ring. My o ring bunches up. I don’t know where to get the o ring.

The O-ring sits in a recess in the chainring. I had to use a pick to get it out for the photo. It then went back without any argument and seemed to tighten up fine. Of course, I then discovered that my torque wrench had died (I think it might be out of guarantee - I bought it in 1976), so had to "guess" the tightening torque by using another wrench to tighten then undo until I got somewhere around the 25Nm. I've used locktite, so it should hold okay.

I had another look at the R2 site. The hexagon fixing says "Brose" in the middle, and the two microspline rings say "Shimano". I guess they are, as you say, just generic pictures. At least I can see the offset on the bottom photos, so I'll give it a try. It's not a huge amount of cash.

[Edit: Given the cost of postage, I ordered the rear cassette and a couple of chains at the same time as the prices were within a euro or two of the same items in Spain]

 

[Like a Boss]

The O-ring sits in a recess in the chainring. I had to use a pick to get it out for the photo. It then went back without any argument and seemed to tighten up fine. Of course, I then discovered that my torque wrench had died (I think it might be out of guarantee - I bought it in 1976), so had to "guess" the tightening torque by using another wrench to tighten then undo until I got somewhere around the 25Nm. I've used locktite, so it should hold okay.

I had another look at the R2 site. The hexagon fixing says "Brose" in the middle, and the two microspline rings say "Shimano". I guess they are, as you say, just generic pictures. At least I can see the offset on the bottom photos, so I'll give it a try. It's not a huge amount of cash.

[Edit: Given the cost of postage, I ordered the rear cassette and a couple of chains at the same time as the prices were within a euro or two of the same items in Spain]

GP I forgot to mention, the chain guide will need spacers if you change the sprocket..... e13 sells a kit, but it has been out of stock. some appropriate washers would work. The 9.8 XT bike has a 52mm chain line, the 9.9 XTR bike has the fancier sprocket with a 53mm chain line. So that must be taken into account with that chain guide or else it will rub.

 

[GrahamPaul]

GP I forgot to mention, the chain guide will need spacers if you change the sprocket..... e13 sells a kit, but it has been out of stock. some appropriate washers would work. The 9.8 XT bike has a 52mm chain line, the 9.9 XTR bike has the fancier sprocket with a 53mm chain line. So that must be taken into account with that chain guide or else it will rub.

Thanks. I'll keep that in mind. At least it's more space, not less...

 

[HORSPWR]

Same as you do for changing a rear cassette or a bottom bracket, no?

Tool for every job...

Not really, BB and rear cassette tools are cheap and everywhere. From the posts here the chainring tool is neither easy to get a hold of or cheap!
And really, how hard was it for them to have a spider that fitted up to a 104BCD chainring?

 

[Dr. Ergal]

I had another look at the R2 site. The hexagon fixing says "Brose" in the middle, and the two microspline rings say "Shimano". I guess they are, as you say, just generic pictures. At least I can see the offset on the bottom photos, so I'll give it a try. It's not a huge amount of cash.

I can confirm that the tool for Brose lockring is suitable for Gen4 also
Just re-tightened mine to my brand new Level, just after the first ride...

I'm looking for a solution, 'cause I'm pretty sure it will get loosen again soon
So far, I just applied a lot of medium Loctite... ?

 

[Dr. Ergal]

Hereinafter my personal interpretation of the topic
To avoid toduplicate posts, I just put the linkof the post

Bosch CX gen 4 chainring nut

Chainring nut / spider nut or other names... Has anyone experienced their chainring nut coming loose? Today is the first day my Rail has let me down, I had to cut my ride short today when I felt a vibration at my feet, checked the chainring and it was wobbling and the spider nut had come...

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