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Worth upgrading from older high end Jamis to newer tech?

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Worth upgrading from older high end Jamis to newer tech?

Old 12-12-22, 07:13 AM
  #51  
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Originally Posted by 79pmooney
I'm another who will stick to round seatposts (and preferably bikes that take or can be shimmed to 27.2mm). Seatposts have to work or the bike is completely unrideable. (I rode my first Cycle Oregon on my newish custom with an old Avocet head pressed onto a ti tube for the post. (Avocet for its big setback.) The head broke on day one. Fortunately 3 miles from the finish and I just rode it out-of-the-saddle. A mechanic lent me a Kalloy that I used for nearly a year while I had a custom post made. Simple fix. Not perfect. It was a real blessing to get my seat position back when I go the new post! but it worked and was fully rideable and nothing makeshift about it.

This on a bike with large diameter tubes but they were round and the builder had no issue at all with providing the 27.2 shim.
Are you aware that the Defy will also accept a round seat post?

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Old 12-12-22, 01:26 PM
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Originally Posted by PeteHski
You worry too much. These are non-issues for 99% of Defy owners. The D-post concept works and that's one of the attractions of this particular bike. It's not for everyone, but worrying about not being able to source a seatpost for my Defy is not something I lose sleep over. If it was a more niche brand then maybe it could be more of a potential issue. But Giant parts, including discontinued parts, are relatively easy to source online. There are even several third party suppliers who specialise in Giant spares. There are a lot of Giant bikes out there, so the demand for spares is not going to dry up overnight.
I am not loosing sleep over it either. Just explaining why someone might want a different seatpost and why proprietary stuff isn't great. Maybe it won't dry up overnight but companies frequently do odd things and discontinue stuff people liked or used.

I do worry but just a normal amount.
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Old 12-13-22, 11:28 AM
  #53  
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I am still curious to know how many Defy owners in the world are sitting there wishing they could put a dropper post or a thudbuster on their bike. If the genuine answer is more than single digits, I would be shocked.
That seems like such a weak reason to complain specifically about a Defy seatpost, and this is coming from someone who has little love for proprietary anything.
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Old 12-16-22, 09:37 AM
  #54  
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Originally Posted by mstateglfr
I am still curious to know how many Defy owners in the world are sitting there wishing they could put a dropper post or a thudbuster on their bike.
3

Glad I could help.
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Old 12-16-22, 09:56 AM
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^ Ha, good thing veganbikes is advocating for their inclusion.
"WONT SOMEBODY THINK ABOUT THE POOR CYCLISTS WHO WANT A DROPPER OR THUDBUSTER ON THEIR CARBON DEFY ROAD BIKE?!?! THOSE POOR MARGINALIZED SOULS!"
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Old 12-16-22, 11:28 AM
  #56  
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Originally Posted by Kapusta
3

Glad I could help.
Those 3 guys should have done their research before buying a Defy too. Although they are in luck as I believe there is an adaptor shim you can use to fit a round post. I bet those sell like hotcakes!
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Old 12-17-22, 04:05 PM
  #57  
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Originally Posted by PeteHski
Those 3 guys should have done their research before buying a Defy too. Although they are in luck as I believe there is an adaptor shim you can use to fit a round post. I bet those sell like hotcakes!
The problem would be in locating an adapter 10 years from now when you need a new seat post and can't get one of those D shaped ones either. I wouldn't think anyone would need anything except the stock post for quite a while, but accidents happen eventually.
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Old 12-17-22, 07:04 PM
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responding to the original question, IMO you have most of the items that are game changers (carbon frame, electronic shifting, aero wheels), except one: disc brakes. my experience has been that disc brakes make an enormous difference. also, it's likely that your frame will be vastly better as well. and hey, you can't take it with you.
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Old 12-18-22, 08:08 AM
  #59  
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Originally Posted by RH Clark
The problem would be in locating an adapter 10 years from now when you need a new seat post and can't get one of those D shaped ones either. I wouldn't think anyone would need anything except the stock post for quite a while, but accidents happen eventually.
Obsolete parts supply for Giant bikes really is a non-issue. I get it that you prefer to avoid proprietary parts, but you are just making up an issue that doesn't actually exist. This is not some obscure bike brand we are talking about. Giant spares are easy to find for any vintage.
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Old 12-18-22, 05:49 PM
  #60  
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PeteHski the issue doesn't exist now that is correct but one does not know the future. Specialized no longer makes Zertz inserts or some older clamps and some other parts, they are not a small manufacturer. Things do happen. I get that you don't want it to be so and maybe it won't but being aware of it is important. Saying it won't happen is silly unless you are a in the upper echelons of Giant and have worked there a long time and know the plan for small parts like that. You are potentially right that maybe no it won't happen they have been using these awhile but things can get discontinued and do get discontinued in the bike industry and finding some parts that maybe common at the time later down the road can possibly get tough.
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Old 12-18-22, 11:11 PM
  #61  
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Originally Posted by gene99
responding to the original question, IMO you have most of the items that are game changers (carbon frame, electronic shifting, aero wheels), except one: disc brakes. my experience has been that disc brakes make an enormous difference. also, it's likely that your frame will be vastly better as well. and hey, you can't take it with you.
Just to balance opinions - long time good quality rim brake user here and recent disc brake user. I don't think that discs are game changers for road bikes at all. There are some advantages, but also disadvantages. They're fine and I won't argue against them, but not game changers, and not reason enough to "upgrade" a bike. There might be others and discs are likely to be a standard feature and that's not a problem, just not a huge advantage imo.

To me, proprietary parts without substitutes (like any shaped seat post being discussed) would be big red flags.

Last edited by Camilo; 12-18-22 at 11:16 PM.
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Old 12-19-22, 06:03 AM
  #62  
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Originally Posted by veganbikes
PeteHski the issue doesn't exist now that is correct but one does not know the future. Specialized no longer makes Zertz inserts or some older clamps and some other parts, they are not a small manufacturer. Things do happen. I get that you don't want it to be so and maybe it won't but being aware of it is important. Saying it won't happen is silly unless you are a in the upper echelons of Giant and have worked there a long time and know the plan for small parts like that. You are potentially right that maybe no it won't happen they have been using these awhile but things can get discontinued and do get discontinued in the bike industry and finding some parts that maybe common at the time later down the road can possibly get tough.
I was actually basing my future prediction on the basis of being able to easily buy obsolete Giant parts for older bikes today. Parts way more obsure than a seatpost too. Anyway we can come back in 10 years and see if I can still buy a D-shaped seatpost for a Defy.

Just because parts may become discontinued doesn't mean they instantly become impossible to source. In the case of the Giant D-posts, there are thousands of them out there and therefore likely to be obtainable for a very long time. Given that people rarely need to buy a replacement seatpost implies that there will be ample NOS parts available for years after they eventually become obsolete. We also live in an age where we can buy parts from literally anywhere across the globe, so I don't need to rely on my LBS to stock obsolete parts.

If I was paranoid about this I would simply buy a spare seatpost today (which I'm not going to do btw).
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Old 12-19-22, 08:13 AM
  #63  
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he's got carbon wheels, which mean cork brake pads. if you don't think disc brakes aren't a huge benefit over caliper/cork pad brakes maybe you need to ride more. and i'm curious, what are the disadvantages of disc brakes, except maybe for a few additional ounces of weight?
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Old 12-19-22, 08:30 AM
  #64  
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Please don't turn this into a disc v rim brake debate
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Old 12-19-22, 01:41 PM
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Originally Posted by Germany_chris
Please don't turn this into a disc v rim brake debate
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Old 12-19-22, 08:18 PM
  #66  
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Originally Posted by gene99
he's got carbon wheels, which mean cork brake pads. if you don't think disc brakes aren't a huge benefit over caliper/cork pad brakes maybe you need to ride more. and i'm curious, what are the disadvantages of disc brakes, except maybe for a few additional ounces of weight?
Yeah, I've never used rim brakes with cork pads (or other specialty pads) on CF brake tracks. So I won't argue with that. I was just saying that in my experience, discs in and of themselves are not a "game changer". Your experience is obviously different.

Originally Posted by Germany_chris
Please don't turn this into a disc v rim brake debate
I think it's at least somewhat relevant in that the OP was asking whether it would be worthwhile upgrading from his current bike. One of the "upgrades' would likely be disc brakes vs. rim brakes. So people are giving opinions on what they think the advantages and disadvantages of the various features on the new bike and it's fair to hear more than one opionion. It's no more devolved into a disc vs. rim than a round vs not-round seatpost. Both are relevant to the discussion.

Last edited by Camilo; 12-19-22 at 08:27 PM.
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Old 12-19-22, 08:41 PM
  #67  
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Originally Posted by Dictatorsaurus
I have a 2011 Jamis Xenith Team carbon DA di2 with Reynolds carbon 44/66 wheels (rim brakes)

I've been tempted to get the 2021 Giant Defy Ultegra di2. They retail for $6,500 which is quite a bit. I don't know how much I would get for my Jamis.

A few things I'm considering

- I like disc brakes
- Whole internal cable routing on the Defy
- Allows for wider tires
- Wheels are tubeless
- Giant D-Fuse seatpost provides noticeable comfort with around 12mm swing.

My Jamis was top build over ten years ago. With technology changing, would the newer Defy be a noticeable upgrade?

Here's my Jamis:
The new bike would be an expensive downgrade.
  • Discs would add 2 pounds to the bike, between the rotors, extra frame and fork reinforcements and the heavier wheels. Are you riding on steep downhills in the rain with racks and camping gear with arthritic hands? If not, then discs on the road are heavy, fussy and unnecessary.
  • You actually want internal cable routing? It kind of looks kewl, until you break a cable and spend 3 hours of misery to replace it, including taking the crankset and bottom bracket out.
  • Wider tires (>25mm) are heavy, slow and less aero - a significant performance downgrade. If you are heavy and riding on gravel, maybe.
  • Tubeless: are you getting many flats per year? If not, tubeless is a PITA. Mounting tires on tubeless-compatible rims is hell.
  • Giant D-Fuse seatpost... I've got one of these on a disc-brake equipped TCX. I don't notice any difference over a standard carbon post, only that I had to pay some extortionist fee for the D-Fuse post and stupid proprietary stem.
Recommendation: find another rim-brake Jamis Team from about 10 years ago, except one size larger, and fitted with low-profile alu rims.
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Old 12-19-22, 09:11 PM
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^. Let the games begin!
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Old 12-19-22, 11:59 PM
  #69  
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Originally Posted by Dave Mayer
  • Wider tires (>25mm) are heavy, slow and less aero - a significant performance downgrade. If you are heavy and riding on gravel, maybe.
What? You do realize it is 2022 not the 1970s and 80s correct? Wider tires are more aero and faster and potentially marginally heavier but not enough to make any difference for anyone realistically unless you are building a British Hill Climb bike to be the absolute lightest ever but most of those are ridiculous machines for one purpose and one purpose only getting up a hill as fast as possible. You should try some wider tires and enjoy yourself. The bumps and vibrations you are feeling on skinny tires is NOT speed but you going slower and being less comfortable which your brain is telling you has to be speed because speed must be felt but in reality, not the case.

I won't bother so much with the other stuff because I really don't care on disc or rim brakes, like I have said and will continue to say until Cane Creek stops making the eeBrakes rim brakes are still fine. I have them on two different bikes and not complaining but I also love disc brakes as well and have those on several bikes.

Internal routing can suck badly it depends on the bike, a lot of newer bikes are designed with internal cable routing in mind so it is less faff but I am fine with or without it. Same with tubeless with or without. And I think people know my stance on D-fuse.

I wasn't aware of a stem issue aside from the old thing they did for a reservoir at the stem so you could run cables to the stem and hydraulic the rest of the way but this was before hydraulic disc brakes on road bikes was as common. That was stupid and like most companies I am sure they have a version of a one piece bar and stem but Tom Sturdy does it out of titanium and it is sexy as hell and honestly if he can print it up to my specs I will take it.
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Old 12-20-22, 01:30 AM
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Originally Posted by veganbikes
What? You do realize it is 2022 not the 1970s and 80s correct? Wider tires are more aero and faster and potentially marginally heavier but not enough to make any difference for anyone realistically unless you are building a British Hill Climb bike to be the absolute lightest ever but most of those are ridiculous machines for one purpose and one purpose only getting up a hill as fast as possible. You should try some wider tires and enjoy yourself. The bumps and vibrations you are feeling on skinny tires is NOT speed but you going slower and being less comfortable which your brain is telling you has to be speed because speed must be felt but in reality, not the case.
I do have a bike with wider tires: 32mm Conti GP5000s. They ride like a farm tractor.

Look at the rolling resistance test results for these tires at different sizes - easy to Google. On non third-world pavement, at recommended inflation pressures, the 23s and 25s have the lowest losses (watts). Nevertheless, overall rolling resistance is trivial, with only a small number of watts between them. The biggest handicap of wider tires is the complementary wide heavy rims used on disc brake bikes. Plus the greater number of crossed spokes required to handle the extra forces discs place on wheels. You need fast wheels: then you'll be on 23mm carbon (rim brake) tubulars.

BTW: wide tires have to have more air resistance than narrow tires, as they have more frontal area.
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Old 12-20-22, 01:55 AM
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Well at least it didn't turn into a disc v rim, we decided to kick the other dead horse wide v narrow tires
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Old 12-20-22, 04:18 AM
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gene99 I am genuinely curious, can you explain what makes disc brakes a game changer for you? Can you describe the type of riding you do that led you to that conclusion?

Camilo I think I'm with you overall; I'm struggling to recall instances where I have felt disc brakes were a game changer. I will say that while I get by just fine on carbon rims with rim brakes, they don't inspire confidence on long steep twisty descents. In fact now that I think about it, I especially dislike doing some of the local hill repeats on my carbon rim brake wheels - it feels like I'm just wearing out the pads and yes those descents, while not super long, can be steep and twisty enough such that I'd be riding my brakes almost the whole way down (it doesn't help that I'm a bigger dude at almost 200lbs). But those situations feel fine when I run rim brakes on alloy wheels. Otherwise, on most normal road rides my carbon rim brakes feel just fine, even with extended descending as long as it's not super steep with lots of twists. I've ridden disc in their early days, both MTB and road, and they've always just felt heavy to me, too heavy to justify the stopping gains they offered. I'm sure modern disc setups are lighter and have better modulation feel at the levers, but I've not been curious enough to get a new bike just to have disc.

Dave Mayer I would agree that if you are comparing 32mm tires to 23mm tires, then the wider tire is substantially heavier and slower to spin up. I feel like the threshold is at 28-30mm, under which I do not notice the weight penalty beyond the 25mm tires I typically run (true width 26-27mm on modern rims).

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Old 12-20-22, 08:05 AM
  #73  
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[QUOTE][/gene99 I am genuinely curious, can you explain what makes disc brakes a game changer for you? Can you describe the type of riding you do that led you to that conclusion?QUOTE]

what Camilo said. another thing I'd add, -- after having had mechanical discs on several off-road bikes -- is that hydraulic discs are almost a game changer on their own.

i was thinking about the switch for a while, but finally decided to do it after riding near my brother-in-law's house in Northampton, MA on a damp morning and realized how terrified I was on long descents. where I ride in Long Island the hills are short, but can be very steep, and there's usually a light or stop sign at the bottom. now, instead of worrying about braking I attack the downhill (fun for me). it was worth it to me to make the switch, to the tune of about $12k. (of course you can buy a great disc brake bike for a lot less.) everyone has to decide themselves whether it's "worth it" to them. it was to me.

my new baby...
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Old 12-20-22, 08:06 AM
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Thank you all for your extensive feedback.

I decided to keep the Jamis for the following reason.

- I only paid $3k for the Jamis brand new on closeout.
- Despite all the talk about stack height and steerer length, the bike fits me like a glove. If anything, I might consider a 10mm shorter stem for more comfort.
- I don't ride in the rain. If it happens to rain during a ride, I'll take it slow and leave longer distances to stop
- Just installed GP5000 28mm. With my narrow 14mm Reynold rims, it comes to around 25mm. I think with some riding it will stretch to 26mm. I can live with that.
- DA di2 is hard to walk away from. Anything comparable nowadays would be north of $8K.
- The high end defy would be at least 2 to 3 lbs heavier.

As one said above, the Defy might be an expensive downgrade.
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Old 12-20-22, 09:09 AM
  #75  
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Originally Posted by Dave Mayer
I do have a bike with wider tires: 32mm Conti GP5000s. They ride like a farm tractor.

Look at the rolling resistance test results for these tires at different sizes - easy to Google. On non third-world pavement, at recommended inflation pressures, the 23s and 25s have the lowest losses (watts). Nevertheless, overall rolling resistance is trivial, with only a small number of watts between them. The biggest handicap of wider tires is the complementary wide heavy rims used on disc brake bikes. Plus the greater number of crossed spokes required to handle the extra forces discs place on wheels. You need fast wheels: then you'll be on 23mm carbon (rim brake) tubulars.

BTW: wide tires have to have more air resistance than narrow tires, as they have more frontal area.
Using Silca recommended psi for my body+bike weight, I should ride a high performance tube tire in 23mm at 110psi, 25mm tire at 97psi, 28mm at 81psi, and 32mm at 66psi.
So given this info, if I look at the rolling resistance chart I get these resistance numbers at the psi and widths above- https://www.bicyclerollingresistance...000-comparison
23mm - 10.3 watts
25mm - 10.8 watts
28mm - 11.5 watts
32mm - 12.2 watts

So less than 2 watts difference between a 23mm tire and 32mm tire when proper inflation is accounted for.
Meanwhile, each tire is 80 grams difference in weight.
So a 23mm tire saves 1.9 watts and weighs 80g less, which is 2.8oz. That simply is of no consequence to almost anyone. I could push myself for a couple hours on a 40mi course and not notice the difference in weight or watts. Its happened many times and I dont notice the difference. Even after 2.25 hours of hard effort, there just isnt enough of a difference for me to have noticed from an in use perspective.

As for wheel weight, more spokes arent required. There are tons of 20/24 and 24/24 spoke disc brake wheels. Zipp 303 Firecrest is a popular disc wheel and weighs 1350g. $650 BTLOS 39mm wheels with basic bitex hubs and 24/24 lacing of basic butted spokes only weighs 1600g, so that drops quickly as cost increases.
These weights are lighter than probably 85% of rim brake wheelsets that are currently used on road bikes. And again, the BTLOS wheens could easily drop weight with some changes to the basic lowest level options I selected.
Worth noting, a similar BTLOS rim profile and matching components in rim brake version weighs 1543g. So...65g is what we are talking about here.


I could ride 23mm tires on rim brake wheels or 32mm tires on disc brake wheels and the difference would be 225g between tires and wheels. I wont be any slower due to wind resistance because I cant hold some perfectly aero position for an entire ride and that argument goes right out the door after that. Perhaps I would feel less fatigue over 40mi on 32mm tires though.
hm...


There is no right or wrong way to ride. Its just absurd to claim absolutes while providing little to no actual evidence. Furthermore, when not everyone rides the same way or for the same goals, its quite difficult to compare apples to apples.

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