Mullet on a Bosch gen4

[Bomble]

Just in the process of mulletting my Rail, will i need to take it in for a change of the wheel circumference? Is it even possible on the Gen 4?

 

[Mteam]

Yes you'll need to get a bosch dealer to change the circumference value when changing from 29 to 27.5 wheels

 

[Bomble]

Cheers?

 

[Sijmes]

Yes you'll need to get a bosch dealer to change the circumference value when changing from 29 to 27.5 wheels

Every shop that I have rang claim that this isn't possible ?

 

[davosaurusrex]

Ask Rob, he did it on the Focus Sam2 review, didn't mention changing anything though

 

[Sijmes]

Ive sent him a message, cheers

 

[Doomanic]

I've done it.

I had to get the shop to change the wheel circumference. The smaller you can get them to make it, the higher your assistance cut off will be.

 

[Sijmes]

I've done it.

I had the get the shop to change the wheel circumference. The smaller you can get them to make it, the higher your assistance cut off will be.

I'll get my LBS to change it, I assume the same setting has to be entered into the kiox display as well.

 

[Mteam]

I'll get my LBS to change it, I assume the same setting has to be entered into the kiox display as well.

Kiox takes its setting from the motor. And then let's you adjust it within a small range to get the speed display accurate.

 

[B00ST]

Just FYI:

I have a Scott Ransom Eride 920. I had to talk to Bosch and Scott to get my 27.5 configured. A Bosch authorized dealer can only change the wheel size up or down 5% which is not enough for a 27.5 wheel which. To make a long story short, Bosch had to ask permission from Scott, then Scott remoted in to the Bosch authorized dealer with Bosch Corp on supervising on the phone. The tech said, Scott had to put their parameters in.

Others may have to get the manufacture involved because an Bosch authorized dealer has limited access.

 

[Doomanic]

I watched the dealer do mine. No contact with Trek or Bosch. We just worked out the wheel circumference with a calculator and used the Bosch Dealer Portal to set that size in my firmware.

 

[B00ST]

I wish mine worked out that way. On my first visit to the shop, we did the same. We measured the wheel by rolling it until it was a full rotation and entered measurement to Bosch software. When I got home, I noticed I was topping out quick on my limiter (20mph). I downloaded speed app and noticed my speed was off 1.5 - 2 mph. When I hit 3/4 of a mile, my bike showed I was already at 1 mile.

Maybe Scott has there's locked down? My suggestion is to download a speed app and verify speed and mileage is the same.

 

[Doomanic]

You don't enter the information anywhere; it's a slide bar that you adjust.

 

[B00ST]

You're right! You only get 5% to adjust the wheel circumference which is not enough.

 

[Doomanic]

Your dealer must have been on the wrong screen. It's a hell of a lot more than 5% and it's shown as wheel circumference in mm (in the UK)

 

[millemille]

Had the settings in the software of my Focus Sam2 adjusted yesterday to compensate for the 27.5" rear wheel by my LBS.

With laptop plugged in and wheel circumference measured it's a simple process to enter the wheel circumference in mm and a slide bar shows where you are between the maximum and minimum diameters the software can cope with.

A 27.5" wheel with a 2.6" tyre is nowhere near the limits of the circumference the software can cope with.

 

[B00ST]

It's possible but if that was true then I would imagine Bosch would just tell the tech to make that change.

 

[Doomanic]

but if that was true

What possible reason is there for us to lie about it? Of course it’s true.

 

[Chairman]

I have the same issues with my cannondale moterra 1. Medium frame. My bike shop whi are very said bosch wont allow it. I went directly ti cannondale because they already have a 27.5 in small frame and they also refused. In fact it got worse. They said they wouldn't warranty because of the non standard modification. WTF is happening here

 

[LowStandards]

LBS changed mine in a few moments when I went 27.5 on the Rail


Another LBS did the same as I stood in front of them after a new motor was fitted

 

[Chairman]

Ok i dont get it then. I am being told by Cannondale that Bosch wont even cover warranty if I change wheel size. I cant see how Trek and Cannondale can be so different. I will ask Cannondale to please explain and come back to you