Shimano Compatible New Wheels

Sure! If you have the correct spacer a 9 speed cog will work just fine.

gimpy_calfee said:

New Shimano compatible wheels are 10 speed but would a 9 speed cassette fit/work on the free hub for use with a 9 speed bike?

carbonguru said:

Sure! If you have the correct spacer a 9 speed cog will work just fine.

no, probably not. The 10 speed cassette has deeper splines by about 2mm. The new '10-speed only' freehub bodies are made with the 2mm extra spline depth.

Explanation. Alloy freehub bodies, used to save weight, are prone to having notches cut in by the steel cassettes. When Shimano Dura Ace made their 10 speed freehub in 2004, they made the freehub out of alloy. They raised the splines to avoid getting notches cut in. This worked very well with the 10 speed cassette, but the splines were too deep for any other cassette. This is the same on all of the 07 wheels. The 5600, 6600 and 7800/7801/7801SL etc.

So, the deeper spline will not fit the 9 speed spline. Welcome to the world of Shimano. If you want one part, you have to upgrade everything.

Oh, yeah, forgot one thing

[img]excelsports.comShimano%20Dura Ace%20Hub%20Rear%207800.jpgOpen ↗[/img]

See the shallower splines to the right. These would fit 9 speed cogs but only 2-3 of them. These are shallow to accomodate the 11, 12 and 13 tooth cogs which can't have the deep splines because their isn't enough cog.

Here is a good link that elaborates on, and illustrates the aforementioned:

bike.shimano.com9 10sp%20cs fh wh%20compatibility.pdf.pdfOpen ↗

Bobby you are 100% correct. I was thinking 9 speed hub with a 10 speed cassesste.

5. Can I use my current 9-speed hubs with the new 10-speed cassette (CS-7800)?Yes, any 9-speed Shimano free hub (FH) can accept the new cassette. A spacer (provided with the cassette) must be used for adaptation.

13. Can I use my current 9-speed cassettes on the new Dura-Ace wheels (WH-7800)?No, due to the shallow serration associated with existing 9-speed components, all 9-speed cassettes will not fit on to the new aluminum free hub bodies

Here is the link: dura-ace.shimano.comfaq s.htmlOpen ↗

bobbyOCR said:

no, probably not. The 10 speed cassette has deeper splines by about 2mm. The new '10-speed only' freehub bodies are made with the 2mm extra spline depth.

Explanation. Alloy freehub bodies, used to save weight, are prone to having notches cut in by the steel cassettes. When Shimano Dura Ace made their 10 speed freehub in 2004, they made the freehub out of alloy. They raised the splines to avoid getting notches cut in. This worked very well with the 10 speed cassette, but the splines were too deep for any other cassette. This is the same on all of the 07 wheels. The 5600, 6600 and 7800/7801/7801SL etc.

So, the deeper spline will not fit the 9 speed spline. Welcome to the world of Shimano. If you want one part, you have to upgrade everything.

Oh, yeah, forgot one thing

[img]excelsports.comShimano%20Dura Ace%20Hub%20Rear%207800.jpgOpen ↗[/img]

See the shallower splines to the right. These would fit 9 speed cogs but only 2-3 of them. These are shallow to accomodate the 11, 12 and 13 tooth cogs which can't have the deep splines because their isn't enough cog.