[-dustin]

i'm just curious....seeing the IH Porter, and the Turner Rail, both frames being 5" or less with 1.5 headtubes, does a headtube with reducers become stronger than a gusseted headtube?

are there any real numbers on this? just curious. if it does, why don't frame manufacturers utilitize a 1.5 with reducers installed?

 

[Bicyclist]

I don't like that setup purely because of asthetics, although it may be stronger. If everyone were to go to 1.5" HTs then forks may as well be 1.5" too.

 

[Mike Buell]

1.5 headtube w/ 1.5-1 1/8 headset allows for stronger bigger bearings.

 

[davep]

Most likely stonger due to much larger weld area between head tube and top/down tubes.

For me, the best part is being able to run almost a zero stack headset, keeps the angles correct and the bars low. With forks getting longer and longer this is a big deal.

 

[RaID]

Most likely stonger due to much larger weld area between head tube and top/down tubes.

1.5 headtube w/ 1.5-1 1/8 headset allows for stronger bigger bearings.

Combination of above
Even if you run reducing cups and a 1 1/8 headset it is still stronger then a comparable 1 1/8 HT setup.

 

[SuspectDevice]

I just want to point out that both of the frames you just mentioned are no longer in production as 1.5" bikes.... It should tell you something.

1. There is no demand for 1.5"
2. Simpler is better. It is not hard to turn a good 1.125" headtube that is flare-free and ovalisation proof. It is going to be lighter, and there is nothing at all wrong with the bearings available for 1.125" headsets.
3. In an effort to reduce stackheights many companies are using short 1.5" headtubes and sticking reducers in them. This makes the headset bearings very close together and actually puts a fair bit more stress on the headtube area... (Think about the reasons why we all are converting to external bearing BB's)

 

[CrabJoe StretchPants]

1 1/8" headtubes allow for a greater "wrap" of the gussets and welds at the HT/TT/DT junction, thus creating a stronger joint with the rest of the frame. i wish my dhr had a 1 1/8" headtube....

 

[smithyM1]

arent external b/b's used primarily to allow the use of larger bearings,therefore making them more reliable???therefore,the fact 1.5HT's use 1.125 headsets means there is no gain over standard sized headtubes,no?

 

[-dustin]

I just want to point out that both of the frames you just mentioned are no longer in production as 1.5" bikes.... It should tell you something.

1. There is no demand for 1.5"
2. Simpler is better. It is not hard to turn a good 1.125" headtube that is flare-free and ovalisation proof. It is going to be lighter, and there is nothing at all wrong with the bearings available for 1.125" headsets.
3. In an effort to reduce stackheights many companies are using short 1.5" headtubes and sticking reducers in them. This makes the headset bearings very close together and actually puts a fair bit more stress on the headtube area... (Think about the reasons why we all are converting to external bearing BB's)

those are along the lines of what i was thinking. i e-mailed a frame manufacturer about a type of (4") frame i was looking for, and he/she e-mailed me back asking my opinion on some things, including the 1.5 HT vs. a heavier duty 1.125. i said i would rather have 1.125 in the Ventana style.

 

[dante]

I just want to point out that both of the frames you just mentioned are no longer in production as 1.5" bikes.... It should tell you something.

1. There is no demand for 1.5"
2. Simpler is better. It is not hard to turn a good 1.125" headtube that is flare-free and ovalisation proof. It is going to be lighter, and there is nothing at all wrong with the bearings available for 1.125" headsets.
3. In an effort to reduce stackheights many companies are using short 1.5" headtubes and sticking reducers in them. This makes the headset bearings very close together and actually puts a fair bit more stress on the headtube area... (Think about the reasons why we all are converting to external bearing BB's)

swing and a miss.

 

[RD]

swing and a miss.

yeah, I think you're a little off base Mickey.

 

[CrabJoe StretchPants]

swing and a miss.

care to elaborate? (aka back up that statement...)

 

[dante]

care to elaborate? (aka back up that statement...)

well, lets see:

1) No demand - as you can see from the large number of bike companies supporting 1.5, as well as the new RS forks, there *is* quite a demand. (not to mention bent or broken 1 1/8th steerers)
2) you can make a headtube as thick as you want, it's still not going to be "flare and ovalization proof". if you try to compensate by running a steelset, it's probably going to be heavier too.
3) most of the people running internal reducers are running DC forks, since with a SC the knobs of the fork will come into contact with the frame. so this isn't really applicable.

edit: unless this is solely about 4-5" travel bikes, then no it's not really necessary...

 

[kidwoo]

1 1/8" headtubes allow for a greater "wrap" of the gussets and welds at the HT/TT/DT junction, thus creating a stronger joint with the rest of the frame. i wish my dhr had a 1 1/8" headtube....

And Ironically turner put 1.5 headtubes on the 03 and newer DHRs because the old ones were ovalizing.

1.5 on a frame increases surface area and load distribution of headset cups...........it's better.

I wish other companies made 1.5 steerer tubes on their forks. With a single crown you get increased stem contact, a stiffer interface and it's less likely to slip on you.

 

[sanjuro]

I just want to point out that both of the frames you just mentioned are no longer in production as 1.5" bikes.... It should tell you something.

1. There is no demand for 1.5"
2. Simpler is better. It is not hard to turn a good 1.125" headtube that is flare-free and ovalisation proof. It is going to be lighter, and there is nothing at all wrong with the bearings available for 1.125" headsets.
3. In an effort to reduce stackheights many companies are using short 1.5" headtubes and sticking reducers in them. This makes the headset bearings very close together and actually puts a fair bit more stress on the headtube area... (Think about the reasons why we all are converting to external bearing BB's)

Good points. The move to 1.5 head tube was to accomodate, of course, the 1.5 steerer. Any frame design alterations were made for that reason.

I thought there were some advantages with the wider steerer, but since Fox and Marzocchi have proven you can make a strong and light fork (ok, at least Fox can do both) with a 1 1/8 steerer, it does seem to make the 1.5 obsolete.

 

[binary visions]

Gah. I know this was pretty much covered, but:

I1. There is no demand for 1.5"

Wrong. Manitou, Magura, and soon RockShox all are producing 1.5" forks. Many, many frame manufacturers are making 1.5" headtubes. People are buying both the frames and the forks. QED.

2. Simpler is better. It is not hard to turn a good 1.125" headtube that is flare-free and ovalisation proof. It is going to be lighter, and there is nothing at all wrong with the bearings available for 1.125" headsets.

Simpler is better? What does that even mean? How is a larger headtube more complex? A reducing headset has the same number of parts as a 1 1/8" headset.

3. In an effort to reduce stackheights many companies are using short 1.5" headtubes and sticking reducers in them. This makes the headset bearings very close together and actually puts a fair bit more stress on the headtube area... (Think about the reasons why we all are converting to external bearing BB's)

The primary reason people are converting to external bearing BBs is because there's no more room inside the shell for a big spindle AND big bearings. Your argument actually promotes 1.5" headtubes, since it allows larger bearings and larger "spindles" (headtubes) - which is exactly why people are switching to external bearing BBs.

If you're going to claim that the reduced stack height (and increased stress) is still an issue, well, unless you have numbers to show that the increased stress is NOT offset by the significantly increased surface area of the headtube, then I don't buy that it's a problem.

 

[binary visions]

The move to 1.5 head tube was to accomodate, of course, the 1.5 steerer. Any frame design alterations were made for that reason.

I agree that the primary marketing drive for the 1.5 headtube was, as you said, the 1.5 steerer.

However, that is not the real advantage of the 1.5 standard. The real advantage of the 1.5 standard lies in the headtube, which offers significantly more resistance to ovalization, and a lot more surface area to weld it onto the frame. Better strength in headsets and/or reduced stack height are fringe benefits of the headtube size increase as well.

 

[RD]

I agree that the primary marketing drive for the 1.5 headtube was, as you said, the 1.5 steerer.

However, that is not the real advantage of the 1.5 standard. The real advantage of the 1.5 standard lies in the headtube, which offers significantly more resistance to ovalization, and a lot more surface area to weld it onto the frame. Better strength in headsets and/or reduced stack height are fringe benefits of the headtube size increase as well.

exactly

 

[Cant Climb]

However, that is not the real advantage of the 1.5 standard. The real advantage of the 1.5 standard lies in the headtube, which offers significantly more resistance to ovalization, and a lot more surface area to weld it onto the frame. Better strength in headsets and/or reduced stack height are fringe benefits of the headtube size increase as well.

Are people still ovlaizing 1 1/8 headtubes......?....maybe 5 years ago but not now.....from what i have seen, maybe i'm wrong.....

1.5 is great idea but for the consumer it sucks because you cant mix and match forks and frames as easily, . And how is the resale on 1.5 forks.....is the demand really there......?.....

My DHR had 1.5 and the geometry of the bike seemed like Dave Turner was still expecting the extra stack height of the lower cup. The flush cup left the bike way too steep.......the IH Sunday uses the 1.5 the right way.....

 

[kidwoo]

Are people still ovlaizing 1 1/8 headtubes.....

Yes

My DHR had 1.5 and the geometry of the bike seemed like Dave Turner was still expecting the extra stack height of the lower cup. The flush cup left the bike way too steep.......the IH Sunday uses the 1.5 the right way.....

Jeez: You can use a reducing headset that adds about 5-7mm stack height OR use the zero stack reducers.

You can also loosen up the pinch bolts on your fork legs and the world is your oyster.

 

[Cant Climb]

You can also loosen up the pinch bolts on your fork legs and the world is your oyster.

True....now i am remembering why i switched back to 1 1/8 and the reducer cups. I tried the zero-stack to try to get lower and it was too steep. I could have adjusted the stanction tubes to put it back to the same geometry with the zero-stack.......but didn't do this because the Chris King headset was soooooo much smoother. :hot:

So there's another reason for 1 1/8........Chris King doesn't make a 1.5 specific headset......:hot:

 

[SuspectDevice]

Exactly like Dante, RD and BV have said, to have any real advantages with a 1.5" headtube you need to change your downtube and toptube spec to gain structural benefits. This is fine if you get your bikes built by some mega corporation that has hydroforming facilities, or build enough bikes to get custom extruded butted tubing, but if you just build bikes out of commercially available tubesets, it necessitates commically and excessively large tubes, limiting turning radius with dual-crown forks.

That's why Sinister has abandoned the 1.5" standard, Sinisters 2 different heavy-use 1.125" Headtubes have been completely failure free, and are much more in scale with the tubing they have available to them....

 

[CBJ]

Then who makes the best bearing for the E13 zero stack cups?

 

[kidwoo]

Then who makes the best bearing for the E13 zero stack cups?

I've got fsa and cane creek in two different bikes. They both work and I haven't had any problems with either.

They do however lack that completely indistinguishible trait chris king headsets have that greatly improves the ride. You know like right after you go hauling ass through a rock garden with a bunch of direction changes and you can't help but think to yourself "damn.......this headset RULES!!!"

For some reason I never get that. In fact it screws with how much fun I can have.

 

[CBJ]

My lower bearing didn't like 8 days of Whistler rain and mud.

 

[Cant Climb]

They do however lack that completely indistinguishible trait chris king headsets have that greatly improves the ride. You know like right after you go hauling ass through a rock garden with a bunch of direction changes and you can't help but think to yourself "damn.......this headset RULES!!!"

For some reason I never get that. In fact it screws with how much fun I can have.

real funny......but i can feel the difference....

 

[dw]

I just want to point out that both of the frames you just mentioned are no longer in production as 1.5" bikes.... It should tell you something.

1. There is no demand for 1.5"
2. Simpler is better. It is not hard to turn a good 1.125" headtube that is flare-free and ovalisation proof. It is going to be lighter, and there is nothing at all wrong with the bearings available for 1.125" headsets.
3. In an effort to reduce stackheights many companies are using short 1.5" headtubes and sticking reducers in them. This makes the headset bearings very close together and actually puts a fair bit more stress on the headtube area... (Think about the reasons why we all are converting to external bearing BB's)

Not really on 3 counts Mickey

1) The demand for 1.5 is alive, well, and growing for sure. In addition to Manitou, Rock Shox and Marzocchi will offer 1.5 forks for the 2007 model year.

2) It is IMPOSSIBLE to build a 1.125 head tube for a 6061 aluminum frame that is "ovalization proof" The bearing contact area is too small to mitigate the largest impacts (regardless of headset press depth). A 1.5 head tube will be stronger for the same weight than a 1.125 head tube. There were almost vloumes written on this a few years ago, complete with calculations, testing data, etc... posted on this board by myself and several others. Search circa 2002.

3) My whole idea behind a reducer headset inside a 1.5 head tube was to allow the use of a longer head tube for the same stack height. This means tubes welded closer to the ends of the head tube for the same bearing load, which translates to better structural efficiency (i.e. lighter weight and more strength). External bearing BB's are not all they are cracked up to be BTW, they will be phased out in favor of cartridge BBs. You heard it here first.

Dave

 

[davep]

Then who makes the best bearing for the E13 zero stack cups?

I am running the FSA orbit IS on both of my mt bikes w/o a problem(with no dust cap/bearing cover). Cane creek makes an IS headset with stainless bearings (the is 8) as well if that matters, but the 'TH' brand bearings that FSA uses seem to last very well.

p.s. I live in the land of rain and make the short trip to whistler quite often FYI.

 

[kidwoo]

My lower bearing didn't like 8 days of Whistler rain and mud.

Yeah in all fairness the only real mud I've ridden in was a few days at whistler on my turner last summer and a few downieville days on my intense. I imagine your locale is a much better test as far as moisture goes.

 

[binary visions]

There were almost vloumes written on this a few years ago, complete with calculations, testing data, etc... posted on this board by myself and several others. Search circa 2002.

I believe they've been pruned out of the database, Dave. I wish I had copied some of those discussions and saved them offline, they were some of the most well-supported discussions that have ever been had on this board.

Nothing like saying, "You're wrong, and here are the numbers to prove it, b*tch."

 

[dw]

Are people still ovlaizing 1 1/8 headtubes......?....maybe 5 years ago but not now.....from what i have seen, maybe i'm wrong.....

I dont have real data on this, but I know that fork AC heights are longer now, and riders are doing stuff that we never dreamed of back in the trail 66 days. The structural properties of 6061 T6 havent changed, and if anything forces have gotten higher. I have seen a LOT of ovalized 1.125 head tubes, thick and thin, but only two ovalized 1.5 head tubes ever.

One thing that I can share quickly is that the prototype Imperial frames used a very thick 1.125 head tube, well before that was in vogue. The design balanced bearing stress failure -vs- elongation failure, equalized them, the best possibel case scenario. A thicker head tueb would not have been stronger, it was designed to the limit of the material. The 1.5 head tube that replaced it was both stronger and lighter. Lots of detailed info on this in the archives. I wish I saved some of those old posts for occasions like this.

Dave

 

[dw]

I believe they've been pruned out of the database, Dave. I wish I had copied some of those discussions and saved them offline, they were some of the most well-supported discussions that have ever been had on this board.

Nothing like saying, "You're wrong, and here are the numbers to prove it, b*tch."

Ahhhhh, the days when I had more than 5 minutes a day to spend online....

 

[Cant Climb]

Yeah in all fairness the only real mud I've ridden in was a few days at whistler on my turner last summer and a few downieville days on my intense. I imagine your locale is a much better test as far as moisture goes.

I been riding the same Chris King headset for 5 years......and its been in hundreds of mud storms out on thE trail.......the thing still works like brand new....

 

[Acadian]

Yeah in all fairness the only real mud I've ridden in was a few days at whistler on my turner last summer and a few downieville days on my intense. I imagine your locale is a much better test as far as moisture goes.

same here..

Although the ones that were on my 05 Sunday were a bit crusty - but I simply took the top blue seal off, rinsed out the bearings with tri-flow, used an air compressor to blow out the grit, re-packed with fresh grease and now they feel like new...

EDIT: I have to admit I was pretty skeptical when ZeroPointFive was first announced - but now I love it – I’m all for it!

 

[dw]

i'm just curious....seeing the IH Porter, and the Turner Rail, both frames being 5" or less with 1.5 headtubes, does a headtube with reducers become stronger than a gusseted headtube?

are there any real numbers on this? just curious. if it does, why don't frame manufacturers utilitize a 1.5 with reducers installed?

There are real numbers on this, and any junior or senior level ME should be able to come up with some support if they understand their schooling.

If done properly, a 1.5 head tube with reducers will be stronger for the same weight than a 1.125 head tube with external headset. Teh 1.5 system also has a higher "possible" strength than the 1.125 system.

Dave

 

[oly]

Ive ran the FSA bearings in my E-13 cups without issue. My new Highline has cane creek bearings since the FSA were sold out at the time... I think they are probably the same bearing anyways... just with different top caps..

To me the only difference between my King headset on my 5-spot and the cartridge bearing headsets ive used on other bikes is not the feel, but lifespan. My king is in its 5th bike... where the other headset bearings only last a year or so... but then again the king was 3 times the price of the other headsets...

 

[dw]

I been riding the same Chris King headset for 5 years......and its been in hundreds of mud storms out on thE trail.......the thing still works like brand new....

Hard to beat a King. I wish they made 1.5 versions.

 

[Cant Climb]

I dont have real data on this, but I know that fork AC heights are longer now, and riders are doing stuff that we never dreamed of back in the trail 66 days. The structural properties of 6061 T6 havent changed, and if anything forces have gotten higher. I have seen a LOT of ovalized 1.125 head tubes, thick and thin, but only two ovalized 1.5 head tubes ever.

Back in the day an ovalized headtube was just something that happened when a bike got to be a year or two old......but i still go to tons of races and meet tons of people and i just dont see it anymore.....why is this if 1 1/8's are getting stressed more with longer A/C/s.....?.....do headsets fit better/tighter.....?......something seems to have changed.....

 

[-dustin]

I believe they've been pruned out of the database, Dave.

too bad. that's pretty much exactly what i was looking for.

 

[kidwoo]

I been riding the same Chris King headset for 5 years......and its been in hundreds of mud storms out on thE trail.......the thing still works like brand new....

What's a mudstorm? That sounds scary.

Please don't feel the need to justify chris king headsets to me.

I have one on my xc bike and one on my dirtjumper. The one on my dirtjumper is older than the FSA bearings in my DHR and feels like it's older. Since that fact has nothing to do with nothing I figured I'd mention it.

I'll gladly buy CK bits though because they're a bunch of hippys who ride bikes to work and recycle just about everything. That's more important to me than the vast differences in headset performance.