Weight Weenieshttp://weightweenies.starbike.com/forum/ Chainsuck on brand new Di2 9070 Venge Boonen Ltd buildhttp://weightweenies.starbike.com/forum/viewtopic.php?f=3&t=116472 Page 3 of 3

 Author: xclemjustinx [ Wed Jun 12, 2013 5:39 pm ] Post subject: Re: Chainsuck on brand new Di2 9070 Venge Boonen Ltd build So your saying the chain length would be the same if your using a 11-23 and a 11-28 cs? What if you were riding a 11-23 and a 11-28 cs and you used the small small configuration for chain length. The two cs configurations would be different thats why you always measure the chain length based off of the biggest cs you are using with the correct rd that can support the maximum tooth allowed for that rd.

 Author: Weenie [ Wed Jun 12, 2013 5:39 pm ] Post subject: Re: Chainsuck on brand new Di2 9070 Venge Boonen Ltd build

 Author: maxxevv [ Wed Jun 12, 2013 6:20 pm ] Post subject: Re: Chainsuck on brand new Di2 9070 Venge Boonen Ltd build xclemjustinx wrote:How can you determine if his chain is too long or too short from that picture? In order to see if his chain is the correct length you must put it in the big chainring and the smallest cog in the rear and see if the pulley wheels are 90 degrees of one another. xclemjustinx wrote:maxxevv wrote:xclemjustinx wrote:How can you determine if his chain is too long or too short from that picture? In order to see if his chain is the correct length you must put it in the big chainring and the smallest cog in the rear and see if the pulley wheels are 90 degrees of one another.Its just a guideline that will work with some but NOT all chainring and cogset combinations. It will work well with a standard 39/53 and 12-25 setup. BUT ... try doing it on a 36/52 and 11-28 setup and you get into problems ... You still need the "small-small" combination check for sufficient chain tension and the "big-big" combination check to check for sufficient chain length (and prevent unnecessary strain on the RD at extreme crossover) to be 100% sure. If you've wrenched enough bikes ( be it hobby or as a job), you'll see all sorts of funny permutations and their quirks. Most of the people here are making a judgement call based on our own experiences. And why not you wait for the original poster to come back to verify our prognosis instead ??I've wrenched more bikes the you can fathom and don't give me that "I've been a bike shop owner for 40 years so I know everything attitude."A standard road bike setup will have the pulleys at a 90 degree of one another. If you are using a MTB then the application is different. I've worked on so many bikes where the chain length was incorrect and the shifting was horrible. Take a look at the installation instructions from Shimano regarding chain install.http://techdocs.shimano.com/media/techd ... 700387.pdf" onclick="window.open(this.href);return false;Dude ... you're talking beyond what you "claim" you know and has done before. Very obviously you're referring to technical manuals and regurgitating/ rehashing what I and others wrote previously above. And just to clarify, there's nothing I can't fathom about how many bikes you've wrenched before. Mainly because it doesn't bother me the least what's the number. The Indian chap working at the Hercules Bikes assembly plant in India for the past 30 years has probably assembled 10 times as many bikes as anyone here on these boards and hell he sure won't know the least bit about assembling bikes with modern derailleurs.....

 Author: Rick [ Wed Jun 12, 2013 6:25 pm ] Post subject: Re: Chainsuck on brand new Di2 9070 Venge Boonen Ltd build The small-small method has been working for me for decades. I actually go small-small, then maybe subtract out one link so the chain has a definite tension in that condition and the chain does not touch the nearly-fully-retracted derailleur cage. The chain can't be "too long" if those conditions hold, and it gives maximum length for available cassettes at the big end.I used it on standard gearing in the past, and am now using it on a 50/34 11-28 and it works fine.But as stated before, you should consider checking derailleur alignment. Modern carbon bikes have bolt-ons with soft aluminum that need to be checked and adjusted.

 Author: xclemjustinx [ Wed Jun 12, 2013 9:59 pm ] Post subject: Re: Chainsuck on brand new Di2 9070 Venge Boonen Ltd build maxxevv wrote:xclemjustinx wrote:How can you determine if his chain is too long or too short from that picture? In order to see if his chain is the correct length you must put it in the big chainring and the smallest cog in the rear and see if the pulley wheels are 90 degrees of one another. xclemjustinx wrote:maxxevv wrote:xclemjustinx wrote:How can you determine if his chain is too long or too short from that picture? In order to see if his chain is the correct length you must put it in the big chainring and the smallest cog in the rear and see if the pulley wheels are 90 degrees of one another.Its just a guideline that will work with some but NOT all chainring and cogset combinations. It will work well with a standard 39/53 and 12-25 setup. BUT ... try doing it on a 36/52 and 11-28 setup and you get into problems ... You still need the "small-small" combination check for sufficient chain tension and the "big-big" combination check to check for sufficient chain length (and prevent unnecessary strain on the RD at extreme crossover) to be 100% sure. If you've wrenched enough bikes ( be it hobby or as a job), you'll see all sorts of funny permutations and their quirks. Most of the people here are making a judgement call based on our own experiences. And why not you wait for the original poster to come back to verify our prognosis instead ??I've wrenched more bikes the you can fathom and don't give me that "I've been a bike shop owner for 40 years so I know everything attitude."A standard road bike setup will have the pulleys at a 90 degree of one another. If you are using a MTB then the application is different. I've worked on so many bikes where the chain length was incorrect and the shifting was horrible. Take a look at the installation instructions from Shimano regarding chain install.http://techdocs.shimano.com/media/techd ... 700387.pdf" onclick="window.open(this.href);return false;" onclick="window.open(this.href);return false;Dude ... you're talking beyond what you "claim" you know and has done before. Very obviously you're referring to technical manuals and regurgitating/ rehashing what I and others wrote previously above. And just to clarify, there's nothing I can't fathom about how many bikes you've wrenched before. Mainly because it doesn't bother me the least what's the number. The Indian chap working at the Hercules Bikes assembly plant in India for the past 30 years has probably assembled 10 times as many bikes as anyone here on these boards and hell he sure won't know the least bit about assembling bikes with modern derailleurs.....You mad bro?!

 Author: tommasini [ Wed Jun 12, 2013 11:16 pm ] Post subject: Re: Chainsuck on brand new Di2 9070 Venge Boonen Ltd build Folks have focused a lot on the chain length (noticed it too) but also I've found in certain situations that chain suck can be caused with perfectly tuned components when too much pedal pressure is applied during a shift from the large ring to the small....such as when that sudden oh sh!t realization comes that the rider needs to quickly downshift and thus the normal pattern of letting off the gas a little doesn't occur.

 Author: jano [ Thu Jun 13, 2013 10:49 pm ] Post subject: Re: Chainsuck on brand new Di2 9070 Venge Boonen Ltd build maxxevv wrote:Dude ... you're talking beyond what you "claim" you know and has done before. Very obviously you're referring to technical manuals and regurgitating/ rehashing what I and others wrote previously above. And just to clarify, there's nothing I can't fathom about how many bikes you've wrenched before. Mainly because it doesn't bother me the least what's the number. The Indian chap working at the Hercules Bikes assembly plant in India for the past 30 years has probably assembled 10 times as many bikes as anyone here on these boards and hell he sure won't know the least bit about assembling bikes with modern derailleurs.....Any reason for you being so aggressive?!BTW he was right in what he said, while you came up only with hot air and some stupid story about an Indian guy...So, if you don't know what you're talking about, why bother and annoy others? Just for the sake of it?

 Author: em3 [ Fri Jun 14, 2013 2:35 am ] Post subject: Re: Chainsuck on brand new Di2 9070 Venge Boonen Ltd build ...only 9 posts on WW and already a TROLL, that was quick.Please do not feed the uninformed TROLL.EM3

 Author: sedluk [ Fri Jun 14, 2013 2:17 pm ] Post subject: Re: Chainsuck on brand new Di2 9070 Venge Boonen Ltd build Shimano recommends the 90 degree method and Campy recommends the small / small method. The way I see it, both are useful. The thing to keep in mind is what cassette are you going to be using and are you planning on using more than one cassette.If you are using a cassette with a large range like 11-28 or 12-29, then it becomes important to not have the chain too loose in S/S and not too tight in L/L. If too loose, when in the S/S the chain will rub on the derailleur. If too tight there will not be enough slack in the chain when L/L.With these large range cassettes you will be right at the limit for both too loose and too tight. You will need to decide how loose is too loose or too tight. The common approach is to work on the too loose and make sure there is just enough tension when S/S and count on the fact that the derailleur was made for these large cassettes and then just double check. If you think about it, it is really the too tight that is the disaster. Ask yourself what would happen if you have a chain that is too tight. But the too tight length is not a very convenient way to get a chain length. This can easily be a problem with a very large aftermarket cassette or hybrid cassettes like a Campy 11-29 that you get when you take a 11-25 and 12-29 and take the bottom of one and the top of the other.Different bikes have different chainstay lengths and chains can only have lengths of even links. So you are kind of limited in the chain length and this will very on different bikes. A good combo might work well on with one chainstay length but not on another when close to the limit. On a Cervelo you can get a very good chain length with a 11-29 cassette with 53/39 and 50/34. With the 52/36 you will end up with a chain that is a little too loose (one link too loose) or else it will be too tight.If you are installing a 11-23 cassette then you will not have the too loose / too tight problem. If you installed the chain using the S/S length. Your chain will not be anywhere near too tight when L/L. In this case the 90 degree method will get you a better chain length. One that will give better shifting. But if you are installing a 11-23 and will be swapping wheels occasionally to a 12-29 for hill climbing then I would recommend the S/S method using the 11-23.In all cases it is good to run through and look at the chain length for both S/S and L/L. This will give you a good idea on how close you are to the limits on both ends. If you install a 12-25 you will not need to be close to the limits on either end. You can still look at both S/S and L/L and get an idea, also look at the 90 degree test and look where you are.Looking at the Venge picture, what people are seeing is a chain that looks loose before you even go to the S/S. I would be surprised if the chain did not rub on the derailleur when S/S. Not a hard problem to solve, but not sure if it will help your chain suck.

 Author: jano [ Fri Jun 14, 2013 8:55 pm ] Post subject: Re: Chainsuck on brand new Di2 9070 Venge Boonen Ltd build Excellent post sedluk!

 Author: maxxevv [ Sat Jun 15, 2013 3:31 am ] Post subject: Re: Chainsuck on brand new Di2 9070 Venge Boonen Ltd build jano wrote:Any reason for you being so aggressive?!BTW he was right in what he said, while you came up only with hot air and some stupid story about an Indian guy...So, if you don't know what you're talking about, why bother and annoy others? Just for the sake of it?Look... who was the one being annoying in the first place ? Read through what I posted previously again, if you know somewhat the installation process is like, you should be able to catch the subtleties and cues. If you need to be fed the details then its probably better you get them from Youtube videos. Basically he was quoting/ rehashing what everybody else was saying after realising his folly. As for the Indian chap, go read up on Hercules bicycles and you'll probably understand why a guy who may have assembled 100,000 bikes over 30 years and not understand the least bit about the modern derailleur installation and its quirks. jano wrote:Excellent post sedluk!I have to give it sedluk to have the patience to post in detail here. I just didn't want to feed the troll. maxxevv wrote:Its just a guideline that will work with some but NOT all chainring and cogset combinations. It will work well with a standard 39/53 and 12-25 setup. BUT ... try doing it on a 36/52 and 11-28 setup and you get into problems ... You still need the "small-small" combination check for sufficient chain tension and the "big-big" combination check to check for sufficient chain length (and prevent unnecessary strain on the RD at extreme crossover) to be 100% sure.

 Author: elSid [ Sat Jun 15, 2013 5:39 am ] Post subject: Re: Chainsuck on brand new Di2 9070 Venge Boonen Ltd build Wonder if xclemjustinx = liggero (recently suspended).This discussion finally shed some light on a problem I've been having with my campy 11 shifters, so thank to all.

 Author: semaj [ Wed Jun 19, 2013 3:34 am ] Post subject: Re: Chainsuck on brand new Di2 9070 Venge Boonen Ltd build jano wrote:Excellent post sedluk!Agreed. Thank you for the nuanced explanation. I always knew about the Shimano way of 90 deg big-small when less than 28 sprocket and big-big + 2 links when 28 or greater, but I didn't know the nuances as to why. Your post clears a lot of things up.