Topic: original front hub w/ GSX-R front end

[sinister902]

for sake of discussion, what about offset rotors? some factory sportbikes use offset rotors up to 18mm of offset....I did mine a little different than gennaro, instead of using the 550 wheel with through bolts I used a later 750 wheel that was 5-bolt pattern and was already threaded...so I have 25mm long bolts mounting the adapter to the hub, with a 12mm wide adapter and an 8mm offset rotor from a VZ800. similarly on my XS750 yamaha triple I posted earlier in the thread, it's the same setup....short bolts holding the rotor adapter into the factory wheel just as the stock rotors were bolted on and there I used RC51 rotors which are also offset (basically what I do is use a 6-bolt rotor in correct diameter on the xs cause the stock rotor was 6-bolt, and on the cb I used a 5-bolt 750 wheel to use a 5-bolt rotor in the same fashion)

I still think in the case of a cb550, the frame strength is going to cause an issue before these front end mods ever could. the frame would fail first.

[ttr400]

Just to clarify, if you are talking about the GSXR600 around 2011 or so.  this bike does not use an aluminium front axle (i don't know of any superbikes that use aluminium for a wheel axle).
Material: Steel
Part #: 54711-14J0
Weight: 376 g
Size: OD 22mm
ID: 17mm
One end OD 28mm, other with M20 thread.

Kevin

[sinister902]

for that, the calculations are bunk as soon as you realize the modulus of elasticity is the same and the cross sectional area is essentially only different by .0001

[FunJimmy]

That's fine if the axle is only stressed by forces transfering through the hub and bearings but the primary reason for large diameter hollow axles is to ensure parralel flex free alignment of the lower stantions. That's even more important with USD forks as there is no provision for a fork brace.

[sinister902]

I understand the design for supersport bikes, that see speeds over 180mph and some serious cornering forces in race situations and trackday situations. But What I'm trying to say here is these cb's with those same suspensions on them are not going to see 180mph and the hard cornering a supersports bike is designed/capable of, at least for 99% of the people doing the swap. Supersports bikes are also not the only bikes that use the inverted forks. In 1994, the first sport bike to use them was the GSXR, which at that time had a solid 20mm axle on 20x42x12 bearings. The 97+ suzuki maurader and boulevard use inverted forks, with a 17mm solid steel axle on 17x40x12 bearings. Are these magically not roadworthy either? I agree that a lesser axle design is dangerous, if all of the variables were the same (I.E. high speeds and hard cornering above and beyond the average rider's capabilities)

I also don't agree with saying there's a lack of provision for a fork brace.... while one wouldn't be small or visually simple, it's not impossible to tie the two caliper mounts and/or fender mounts from the lower stantions together over top of the tire. It would just be large and unattractive and aerodynamically unfavorable.