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Offline Missingtheapex

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Re: F850GS Supermoto Zebra!
« Reply #10 on: July 03, 2020, 01:34:16 PM »
Hi Snodrtrider,


The, Alpina wheels actually were custom made and have the mounting for the stock abs rings. The only thing I can think of is the number of slots on the abs ring need to be different than the OEM ones.

Online SnoDrtRider

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Re: F850GS Supermoto Zebra!
« Reply #11 on: July 03, 2020, 03:55:48 PM »
*Originally Posted by Missingtheapex [+]
Hi Snodrtrider,


The, Alpina wheels actually were custom made and have the mounting for the stock abs rings. The only thing I can think of is the number of slots on the abs ring need to be different than the OEM ones.

That is exactly what the problem is... The original rings on a smaller circumference tire/wheel assembly will spin/rotate faster than with the larger diameter original wheels sending more pulses to the ABS controller than it is expecting.

Just look at the number of slots on my OEM ABS ring vs the one in the photo of the rings that Ron is making...

Count the slots in Ron's ring and count the slots in your OEM rings and you will see the problem... I count 41 on his and only seeing about 1/2 of my ring there are 25 so I am going to guess the oem rings are close to 50 slots.

https://images.850gs.com/7.jpg

« Last Edit: July 03, 2020, 04:03:36 PM by SnoDrtRider »
I don't know where we are... but I have been lost here before...

Offline Tioli

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Re: F850GS Supermoto Zebra!
« Reply #12 on: July 03, 2020, 05:01:41 PM »
Yes interesting you would have to get the sensir input the same for both wheel sizes and that would be the only way.

Dropping from 21" to 17" is going to pull the steering angle in which will tighten the steering up for road  I wonder how that would feel I think it would be OK on a 750 19" to 17" but you are going to loose a little dirt road ability but possibly an acceptable compromise. I also wonder if a different fork angle would need different dampening. In some ways you would think it would as the angle of operation is different and would require less travel to do more dampening.
« Last Edit: July 03, 2020, 05:09:57 PM by Tioli »
Hindsight is a terrible way to learn Id rather be gifted

Offline Missingtheapex

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Re: F850GS Supermoto Zebra!
« Reply #13 on: July 03, 2020, 06:50:55 PM »






It rides amazingly!! I just need to get the stupid electronics to work.🤣
« Last Edit: July 03, 2020, 06:52:20 PM by Missingtheapex »

Offline Tioli

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Re: F850GS Supermoto Zebra!
« Reply #14 on: July 04, 2020, 05:16:43 AM »
Out of curiosity I counted the Front and back slots and diameter for a 750 and they are both the same diameter and both 48 slots 

This says to me the thinking is done in the computer for 21 and 19 front wheels. There may be a setting for 17 front as other model bikes have 17 but how are you going to access it.

I have know knowledge of this but as SnoDrtRider pointed at there is a mathematical formula that will work out what you want to trick the computer into thinking all is good.
Hindsight is a terrible way to learn Id rather be gifted

Offline Newguy

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Re: F850GS Supermoto Zebra!
« Reply #15 on: July 04, 2020, 07:55:31 AM »
*Originally Posted by SnoDrtRider [+]
Pretty sure you will need the special ABS rings due to the wheels being a different diameter than factory.
Hire a machinist.

Offline Missingtheapex

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Re: F850GS Supermoto Zebra!
« Reply #16 on: July 04, 2020, 11:38:51 AM »
*Originally Posted by Tioli [+]
Out of curiosity I counted the Front and back slots and diameter for a 750 and they are both the same diameter and both 48 slots 

This says to me the thinking is done in the computer for 21 and 19 front wheels. There may be a setting for 17 front as other model bikes have 17 but how are you going to access it.

I have know knowledge of this but as SnoDrtRider pointed at there is a mathematical formula that will work out what you want to trick the computer into thinking all is good.

Yes, I counted the slots on Ron's ring and it's 41. What I have done is I ordered the front wheel speed sensor from a BMW1250R. I'm going to take that ring and the original ring to a local machinist and have him make a similar diameter ring that can fit on the mounting points but have the appropriate number of slots to correct the speed reading coming from the sensor.

Online SnoDrtRider

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Re: F850GS Supermoto Zebra!
« Reply #17 on: July 04, 2020, 12:06:02 PM »
*Originally Posted by Ron@BMWMC [+]



The ABS rings are CNC'd from stainless steel and work flawlessly. Wheelie suppression fully functional if desired, ABS braking fully functional, cruise control fully functional.

I will be making these to order, DM me if interested.


I would just contact Ron and see how much he wants for a set of his.... proven and tested.
I don't know where we are... but I have been lost here before...

Offline Missingtheapex

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Re: F850GS Supermoto Zebra!
« Reply #18 on: July 04, 2020, 12:08:33 PM »
*Originally Posted by SnoDrtRider [+]
I would just contact Ron and see how much he wants for a set of his.... proven and tested.

I sent him a message on here with no response. 😭 I hope he does get back to me though as it would be easier to just buy his.

Offline Missingtheapex

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Re: F850GS Supermoto Zebra!
« Reply #19 on: July 15, 2020, 11:05:34 PM »



It works!! Found a local machine shop with a laser cnc and was able to get that done. Everything works now, so happy. Now I just have to get that front fender situation sorted.