[TrailBound29er]

Been searching up and down here for info (in addition to using Google). But I'm starting to get stuck on semantics, I suppose.


I'm assembling a bike from scratch and the next item on my list is the cassette. Since I do not have a parts bike to work with, I have decided to simply leap to the 10 speed. Found a good deal on some new DT Swiss 240 hubs/Mavic 719 Rims (new) and bought them. Like many lightweight rear hubs I was looking at, the DT hubs have an aluminum freehub, which presents a *potential* gouging issue. I've commonly seen the suggestion to purchase the PG-990 Sram cassete or comparable Shimano cassette (in the case of the 9 speeds) or the PG-1080 / M980 units.



Here is where the confusion starts ....


When I look at the pictures of the PG1080 or 1099 ... I only see the small alum blocks on the cassettes that will mesh with the alum freehub. Despite the materials being similar, it seems like a small contact point that would still create a gouging concern. When I look at the Shimano M980 or M771 cassette ... I see 3 sets of blocks that I *assume* are interconnected. But I do not know the composition of those bodies.


Am I looking to deep into the situation? I like the lower prices of the SRAM PG1080 cassette over the Shimano M980 or M771. I haven't fully committed to either lineup yet ... but I'm getting ready to pull the trigger. The drivetrain will be a mix & match depending on the items I find. To me ... I'd rather spend more money on a cassette (for the gouging concerns) and drop one level on a derailleur.


If anyone has feedback or suggestions ... I would greatly appreciate them. If you need more spec setups on the bike, just ask.




Joe

 

[mtnbiker72]

On the Shimano cassettes, the "blocks" are aluminum carriers and will prevent dig in to the freehub body.

 

[TrailBound29er]

On the Shimano cassettes, the "blocks" are aluminum carriers and will prevent dig in to the freehub body.

Cool. That's one question out of the way.

So do we as excessive compulsive neurotics assume that the shimano carriers are less damaging because there is more of them (more surface area)? I'm currently searching google for more info one way or the other. Haven't seen anything on the shimano carriers being aluminum ... so thank you for the info.

Regards,

Joe

 

[mtnbiker72]

The XTR comes with three because the largest 5 cogs are ti and it allows you to replace them without replacing the entire cassette. XT has traditionally put the largest 5 or 6 on one carrier but for 10 speed split it into two...maybe for the same reasons as they do on XTR.

In any event, since it is aluminum on aluminum and it's spread wide there will not be any dig in. You will always get a minor amount from the small cogs much not much.

 

[TrailBound29er]

Noticed that between the XT & XTR cassettes ... thanks for pointing it out tho.


I noticed the XO & XX (Sram) cassettes appear to have all the cogs on 1 spider. So you eliminate that minor gouging at one end of the freehub. But you trade it for more potential gouging when you are in lower gears. :madman:


I may just give DTSwiss in CO a call tomorrow and get some input from them as well.



Please keep thoughts & opinions coming folks .... It's much appreciated. Oh ... and don't worry, there isn't THAT much left on the bike that needs agonizing decisions. Besides tires. That ought to be a fun one too.

 

[TrailBound29er]

Had some correspondence with DT Swiss in Grand Junction today.

Their input was that either of those cassettes should keep galling down and both were suitable. Kind of what I expected ... so no harm.

At this point, I'm leaning towards the M-980 unit. From what I'm gathering .. it appears that the 3 spiders/carriers "interlock" so that it functions closer to that of a single unit. That's cool and all.

I also saw some new locking rings that had the teeth built in already. Assuming it is doable ... that's one more tooth off the splines. Then my last thought was the 3 individual ones ..... couple of possibilities here. Depending on the amount of room, I could run a thin aluminum shim down the length of each spline to spread out the pressure. Another possibility (this one is way out there) is to pin the 3 gears to each other with American Classic's pin kit. That way there are 3 surfaces contact rather than just one. I would think that would spread out the load.

If all that fails ... I'll just look into the steel cassette someday. I know it's not possible to build it right on the first try ... My Jeep is a fantastic example of that. But the closer you get the first time, the easier & more minor changes are. :thumbsup: Until you decide you want a titanium frame. :ihih:

Joe

 

[frdfandc]

DT Swiss does offer a stainless steel free hub body for their 240 hubs. Its not cheap at $120, but its much better at preventing gouging than the aluminum free hub body.

 

[TrailBound29er]

Yup ... that's what I was referring to in my last sentence. I think I saw it somewhere for $99 bucks tho.

I am hoping that if I play my cards right .... it might be a few years before I need that option of the steel body. By then, I'm hoping to have upgraded other areas of the bike I'm unable to afford right now --- that way I can feel less guilt about allllllllllllll that weight of stainless over aluminum. :lol:

Next step .... start looking for the cheapest M-980 cassette I can find. I haven't really studied the XT version closely, other than what MtnBiker72 and I already touched on. Doesn't mean I won't consider it --- not counting grams here, just want to make sure I get the right product in relation to the entire package. :thumbsup:

Joe