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I've found a few threads on Jere about converting the Bulb to accept a 15mm axle.
I realise I have to get the non-disc spacer turned down approx 5mm, but upon getting the 15mm spacers they do not sit flush to the hub body/to the bearing due to a shoulder. See picture below of the 20mm and 15mm spacers side by side.
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On the pro 2 is there a seal that fills the gap between the spacer and hub body? Does anyone have a pro2 15mm they could have a look at for comparison?
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I have done this to mine, you need to turn down the shoulder a bit so it will fit flush in the hub recess. I have some pro2s also, there is no seal other than the o rings that hold them in.
Could you post a picture up? My concern would be that turning the shoulder down would make the spacers undersize for the 100mm spacing as the shoulder is about 2.7mm on each side making 5.4 in total.
Did you turn down the shoulder and the overall length of one of the spacers or did just turning the shoulders down on both bring it into size with the disc aligning OK?
The thing that throws me about the shoulder is that the bearing on the pro2 and bulb are the same so the end cap wouldnt sit flush against the bearing on either hub
Problem fixed compared the spacers to a pro2 and the shoulder also creates a gap on the pro2.
The pro2 and bulb 20mm axle spacers are the same on the disc side but as the bulb has a shorter spacer on the non disc side I had to get the non disc spacer turned down.
The difference in width between the pro2 and bulb bearings was 5.5mm so after machining approximately 5.5mm off the overall length of one of the spacers it slotted into the 15mm forks