what is better? i am thinking of either a 4-bar (specialized) or single pivot (bullit) or a 4 bar like the konas. what do you guys prefer, why?
4-bar vs. single pivot
- Thread starter BEAUster
- Start date
ld prooven design.
No contest... 4 bars (FSR's) have less bad habits on the trail and the maintenance difference isn't a big deal. If you are a big boy and flex the f**k outta bikes, single pivot might be more your style.
4bar+'s
good pedaling
good braking
neutral handling in most situations
4bar-'s
more maintenance
more flex
4bar+'s
good pedaling
good braking
neutral handling in most situations
4bar-'s
more maintenance
more flex
And I'm an awesome lover when I have a 5th of bourbon.p-spec said:
coincidence?
I've just gone from a single pivot to a 4-bar...
I have to say that there are good and bad points.
4-bar:
Great at pedalling thru bumps.
Amazing braking into bumpy corners.
Feels super plush and sensitive to small stuff.
Wicked cornering (could be something to do with above)
No pedal kick-back off big drops.
Single-pivot:
Good for tight techy stuff (ladders and such).
Simple.
Sprints well (but not over bumpy stuff).
Personally I'm big on the 4-bar for really fast stuff and big jumps and drops. For more north shore riding the single pivot might be a little better, though I'm not exactly being held back by my new ride.
I have to say that there are good and bad points.
4-bar:
Great at pedalling thru bumps.
Amazing braking into bumpy corners.
Feels super plush and sensitive to small stuff.
Wicked cornering (could be something to do with above)
No pedal kick-back off big drops.
Single-pivot:
Good for tight techy stuff (ladders and such).
Simple.
Sprints well (but not over bumpy stuff).
Personally I'm big on the 4-bar for really fast stuff and big jumps and drops. For more north shore riding the single pivot might be a little better, though I'm not exactly being held back by my new ride.
One of the newer single pivots that have a roller to deal with chain line and a floating brake might be the best compromise.
I have a BB7 and love it.
The Trek DH bike, PDC DH-one both have similar designs. The super high pivot has a better axle path than a single pivot bike that uses the lower pivot location to achieve better pedaling perfomance. By using a roller, you get the best of both worlds.
I have a BB7 and love it.
The Trek DH bike, PDC DH-one both have similar designs. The super high pivot has a better axle path than a single pivot bike that uses the lower pivot location to achieve better pedaling perfomance. By using a roller, you get the best of both worlds.
Well actually a properly designed single pivot can do anything that a 4 bar horst link bike can. The only exception is braking, a 4 bar horst link brakes slightly better than a single pivot but if you but a floating brake on that single pivot then it exceedingly outperforms the 4 bar horst link. A 4 bar non horst link (konas) perform exactly like a single pivot in all circumstances besides suspension leverage rates.
I do not know exactly what I am talking about but I believe Ive heard from several reliable sources that this is true.
I do not know exactly what I am talking about but I believe Ive heard from several reliable sources that this is true.
If only your reliable sources had stated the same thing.heikkihall said:
I have no opinion, I ride a single pivot.
Depends what you want it for. Racing or riding ? You could do both. But, I think its best fro simply riding.
Had both. Single is way to go for me.
Nothing fancy. Just works. Just make sure you have a quality shock (Again something simple & eventually tuned for your riding)
Had both. Single is way to go for me.
Nothing fancy. Just works. Just make sure you have a quality shock (Again something simple & eventually tuned for your riding)
Only in theory. The reality, in my experience, is that you rarely have to do any maintenance on pivots and stuff anyway - when you do, it's really not much more effort to bang out a couple more and install some new ones.Zark said:
Having ridden a number of singlepivots, linkage-actuated singlepivots (eg Turners, Konas etc), and FSR bikes... there's too much variation to comment
. BB7s are the only singlepivot that I've found to be as plush as most linkage bikes, and I attribute that to the high pivot. IMO bikes like 222s, Bullits etc tend to be pretty harsh compared to linkage bikes (FSR or otherwise). However there are exceptions to this; Konas and Rocky Mountains both have linkages, and they both feel like crap to me. FSR's only real advantage over most singlepivots is the braking, but if you've got a floater then say goodbye to that advantage anyway.IMHO, the actual geometry of the bike matters a lot more than this anyway.
FSR is a four bar, bullit is a single pivot, and the kona's are somewhere in the middle, they are not true four bars due to the location of the pivot at the rear dropout. (Some people call them "faux" bars.) The rear wheel travel path is essentially the same as a single pivot - look closely and you'll see that the axle moves with the chainstay just like a single pivot bike, wherea on an FSR the axle moves with the seat stay. But because of the upper linkage you can tune the shock rate differently than a more simple single pivot. That's my understanding but I'm pretty sure it's accurate. If you search you should find exhaustive descriptions, it's all been laid out in painful detail before, that may be why none of the engineer types are responding (so far anyway).
Maybe someone can link good resources for you? Anyone?
In any event, you will get opinions that are all over the map (some based on experience, many not). IMHO your best bet is to go ride some bikes and figure out what you like better, there are compromises with any design. Some (but not all) of the pedaling performance shortcomings of single pivots can be remedied with a stable platform shock like 5th Element, etc., so the gap is narrowed down.
Maybe someone can link good resources for you? Anyone?
In any event, you will get opinions that are all over the map (some based on experience, many not). IMHO your best bet is to go ride some bikes and figure out what you like better, there are compromises with any design. Some (but not all) of the pedaling performance shortcomings of single pivots can be remedied with a stable platform shock like 5th Element, etc., so the gap is narrowed down.
Back in 2001 when I bought my RFX I chose it over a Bullit since it was far superior at the time since both were offered with a Fox RC shock. Bullit was not a great climber or sprinter with the Fox RC, at least not the ones I tried so it was night and day between it and the RFX, it was also an extra Grand for the RFX but no regrets. In 2002, when the Bullit came with the 5th and 7" of travel the comparison was no longer night and day and I bought my wife a Bullit that she still rides today, both of us still ride these bikes and will for years to come. I've ridden her Bullit on long XC rides when the Fox RC died on my RFX and I have to say that the 5th rocks. I could climb all day in the saddle or stand up and hammer out a long technical climb and it was outperforming my RFX with the Fox. Never put the Fox back on and instead put an Avy on the RFX and it too climbs like a goat.
The craftsmanship of the RFX is in a class of it's own, it's a thing of beauty even today and it's on it's 4th season of hard abuse. I imagine I'll be riding it for the next ten years to come but looking back, the RFX was a $2100 frame in 2001 and the Avy set me back another $550. My wife's Bullit, with the 5th, was $1100 total. Both awesome bikes but very different bank accounts required for similar performance.
The craftsmanship of the RFX is in a class of it's own, it's a thing of beauty even today and it's on it's 4th season of hard abuse. I imagine I'll be riding it for the next ten years to come but looking back, the RFX was a $2100 frame in 2001 and the Avy set me back another $550. My wife's Bullit, with the 5th, was $1100 total. Both awesome bikes but very different bank accounts required for similar performance.
ok, i will be using the bike for dh and freeriding (includes trails). im looking for a bike that pedals well and doesn't feel dead, and can take hit but still has the bump absorbtion these are the type of bikes im looking at
4-bar: bighits, iron horse sgs
single pivots: bullit
other: transition dirtbag (ideal because of price)
please post what you think.
4-bar: bighits, iron horse sgs
single pivots: bullit
other: transition dirtbag (ideal because of price)
please post what you think.
What comes to mine would be the vpfree I think this bike will work for both freeriding and dh.
DEFINATELY a Specialized 4-bar. It pedals better, and it feels better. On a Bullit, when the shock compresses, it affects the chain. It is just a bad design. The Kona suspension gets brake jack (when you use the back brake, the suspension locks up). This is also a bad design. I would only ride an FSR or VPP type linkage.
I had a Big Hit and loved it until it was stolen. I picked up a Bullit cheap and hated it due to all of the pedal feedback and poor braking. I'm on a Nucleon now and love it EXCEPT the braking, which is noticably worse than the Big Hit. I'm considering a floating brake for it but having a really hard time convincing myself that this bike needs more bolts, rods, and linkages.
Most of the FSRs I've ridden (ESPECIALLY the ones actually made by Specialized, eg Bighits, Enduros, s-works DH's) pedal like crap. IH SGS's are *alright* but still could be better IMO.hucker13 said:
I have a two four bar bikes, one trail bike (specialized enduro) and one dh (specialized bighit). The rides of the two bikes are completely different, even though the suspension systems are very similar. The Enduro accelerates and pedals like a hardtail, the bighit does not. At all. What I mean is that one suspension design does not necessarily perform very differently from another, it has at least as much to do with the weight and shock of the particular bike. However, I do like the braking characteristics of four bars. I can drag the rear brake on my bighit all day if I want and the rear end doesn't skip or sink or do anything unsettling. I haven't spent a lot of time on any bikes with fifth element shocks, but I get the feeling (from reading these messages) that the fifth element shock greatly improves pedaling. If this is true, it would probably make a decent-pedaling four bar design great, the same way it improves somewhat poorly-pedaling single pivots. I know that if I keep the compression damping high on my bighit, the pedaling performance increases dramatically, so if that is what a stable-platform shock does, it could mean a dh bike that can be pedalled on trails that aren't all down hill. Differences in suspension design are also probably exagerated by the amount of travel on a bike. If you are looking for a long travel downhill frame, the wheelbase and geometry can change a lot through the range of suspension movement depending on the suspension design. Apparently the wheelbase of the Balfa BB7 grows noticably as the suspension is compressed.
ok, right now i am leaning towards the iron horse sgs. anyone know how much the frame runs? (factory direct)
another thing is why is a single pivot so bad? cedric runs a gemini and seems to fly on it...
and the dirtbag is in my price range, is that system really all that bad?
keep the suspension debates coming
another thing is why is a single pivot so bad? cedric runs a gemini and seems to fly on it...
and the dirtbag is in my price range, is that system really all that bad?
keep the suspension debates coming
There's no reason why a single pivot is "so bad". It's not bad at all. As a matter of fact, the simplicity, potential stiffness, and weight of a single pivot are all great things.BEAUster said:
There are simply disadavantages to a single pivot, just like there are disadvantages to any suspension design. Single pivots have a lot of brake interaction, for one. Single pivots without swing links or linkages of some kind are linear or falling rate designs as well, so to make them progressive, you need a progressive shock.
Nothing wrong with the dirtbag suspension design - lots of companies use it to great success. However, since it looks similar to a Horst link design, people often mistake the two so everyone is usually careful to call attention to the fact that it's really just a single pivot with a linkage to actuate the shock.
put it this way, i am not all that worried about brake jacking... i just want efficient suspension. let's compare the single pivot verse the dirtbag system...
This isn't a very scientific answer but-- Single Pivot with floating brake. Ala my BB7 is heaps better than my Sworks FSR ever was. I didn't help that the FSR's wheelbase was huuuge so it didn't turn in well.
the BB7 feels heaps stiffer and with any luck I wont be getting those cracks in the seat pod that plauge older Sworks.
The BB7 also feels lots plusher could be the shock I know but they are both RC's.
If your just hucking stuff don't bother with the floating rear just go straight single pivot. I you wanna race the get one.
the BB7 feels heaps stiffer and with any luck I wont be getting those cracks in the seat pod that plauge older Sworks.
The BB7 also feels lots plusher could be the shock I know but they are both RC's.
If your just hucking stuff don't bother with the floating rear just go straight single pivot. I you wanna race the get one.
Well... The dirtbag system will have the same pedalling and braking characteristics as a low single pivot. The pivot that connects the chainstays to the frame on the dirtbag is the frame's "single pivot", so a Bullit-type design with a pivot located in the same place will act in the same manner. The linkage just makes the suspension progressive.BEAUster said:
Most Bullit-clone frames tend to have a much higher pivot location, though. That, as I understand it, causes the suspension to lock out somewhat under heavy pedalling.
As far as real efficiency goes, that's a little out of my league - pivot relationships with the chainline and such are better discussed by someone with some engineering background. I'd just be talking out of my ass
Actually I totally agree with you on both counts.thaflyinfatman said:
The FSR's only true advantage is the braking,especially after shocks like 5th's and swingers came out. Brake jack is something I've experienced and don't care for. There's a mental component to it, if brake jack screws you up in the head, better not ride something that has it. Some riders are pinning it so much it wouldn't matter, they aren't on the brakes! Would a bike that doesn't have that trait help their perfomance? Maybe if all other things made it an equal bike (ie has the same geometry, weight, pedaling prowess)
I also agree that actual geometry matters more than the design, to a degree. In the case of the Sworks FSR DH compared to a BB7 that Joe Ray mentioned is a perfect example of this. The FSR DH didn't handle that great, a really long wheelbase made it bus-like in the tight stuff. I'd rather be on the BB7 too in that case!
For me, a linkage actuated single pivot might be an option if it had a floater and the total weight package was equivalent to what I'm on now. In a DH application, its not a stretch, XC it would be tough to make it close enough weight wise. But on on a trail bike where the speeds aren't as fast brake jack seems to matter less.
I've had 4 FSR bikes(M1, Tracer, Big Hit, '98 FSR pro), 2 linkaged single pivots(Giant AC and ATX team), and one single pivot (Y-bike, Ha!). Lets write the y bike off right now, too old to matter! 3-4 FSR's were or are awesome(Big Hit's 24" wheel bugged worse than brake jack!). The AC was fun, but I had to sell it to get off the ATX DH bike. The ATX's pedaling, brake jack and horrible chainguide drove me to get a new bike. I got a Big Hit and was miserable with the performance of it in a DH application. Harsh suspension feel from the 24" wheel hurt it much worse than a little brake interaction would have! My solution? make it a 26" wheel big hit by bolting on an old FSR DH rear end... Franken-bighit! Rode better than with the 24" wheel, but it's boat-like handling after the transformation kinda sucked (48.5" wheelbase, goddamn!). My M1 has the geometry AND the suspension I want. It embodies what I've learned the hard and expensive way. Do your research when buying a bike!
This might be my longest post ever, Whew!
What does it all mean? Bah, I dunno, ride whatever you like! I've made some conclusions over the year in what I like in a bike, just thought I'd share. Can you tell I'm not at work today! Singlepivots aren't "so bad", they have their advantages and disadvantages like everything else. The advantages of singlepivots are usually light weight, simplicity, and stiffness. The tradeoff is poorer braking, (usually) somewhat harsher suspension action (less supple), etc. For this reason they tend to be a bit beginner-unfriendly (no offence to anyone who doesn't like them), because to take advantage of their strong points and neglect their weaknesses, you generally have to be a pretty good rider. For example a 222 isn't often much help to a novice racer, but guys like Peaty are putting the hammer down the whole way down the track, so the stiffness, weight, etc become very important, and the negatives like brake squat are dealt with by the rider.BEAUster said: