Giant TCR Adv Pro 16,000km update.

[@pbt2005]

Mike Burrows is the man who says slack seat tubes equate to a better climbing bike, hence Giants 'modern day' geo. However, I disagree. I too ride a TCR, albeit the SL and the 73 degree seat tube could be half a degree steeper I think. If you look at the pro scene, all the TCR riding guys have a flipped clamp or seat pushed forward to get over the BB. As a machine I like it, it flies around the rolling roads of Devon and overall given the cost, it is a superb machine. Nice review. I read the TCR next gen is due 2020.

[@PeakTorque]

I see what you're saying but bike designers like Burrows often design the frame geometry around their own height. The finer principles are lost when scaling up or down. His ideas of laid back ST angle may be valid but there are just too many variables to muddy the waters of seat tube angle. Chainstay length, saddle setback, reach, all make a difference. But simply, if you're way over the rear of the bike on flat ground, your CoG just gets even further back as soon as there is any incline, and I think for most people that's really awkward and uncomfortable.

[@pbt2005]

I agree. Oddly for one of the worlds best climbing bikes the geo is out of kilter with everyone else, but I assume Giant 'know' what they are doing. The propel is the same. Weird as I usually factor fast aggressive bikes with 73.5 + STA. I also own a Dogma F8 and the TCR kills it going up but the Dogma is a beast on the flat.

[@paulinecolbert1356]

Cycgnr a

[@Robin-kv7gg]

Stumbled across your channel as I was looking to upgrade my XL 2011 TCR to a XL 2019 advanced pro. It sounds like we have virtually the same physical stats. The bike review is educated and in depth. Fascinating insight into things I’d never even considered. Subscribed.

[@angelo16d28]

I was also having a lot of problems with rear wheels and I'm 90 kilo's. Went to 32 spoke (DT Swiss) head Arden hoops with Ultegra hubs. No more problems....

[@PeakTorque]

Great choice i reckon

[@karlwalters3763]

I find your thoughts on the bike being "noodly" rather interesting. I have the 2018 TCR Pro O size large and find it one of the stiffest bikes I've got, and that's in comparison to my Sworks Tarmac and Hi Mod S6. I did notice though, that the frame is very dependent on wheel, stem and hanger choice. At the moment I'm running 58mm deep section carbons 20's front laced radially and 24's back laced radially. The bars that I'm using atm are round aluminium sprinters bars and a fairly tough aluminium 120 stem. I had a set of the Ultegra aluminium rims for a week or two and felt that the bike would wander all over the place when I'd go for the sprint or bombing down a descent. I know it's more of a "hills" bike but I use it predominantly as my criterium bike and actually prefer it over my Sworks Tarmac. Just for perspective, I'm currently sitting at 83kg and can manage to push out a bit over 1400 watts for the sprint in cat 2/1. Keep up the good work and vids! Cheers

[@HCvidz1]

The vinyl wrap looks awesome. I own the exact same bike same year etc and the gripe I’ve always had with it is the horrible neon yellow applied to what otherwise was a nice stealthy looking black frame. Did you do this wrap yourself? I know this is an old vid but would love to know how... and possibly copy 🙄

[@kuanhau4323]

That's one spotlessly clean chain and sprockets. Nice explanation of the real world effects of wheel stiffness in terms of torque and your thoughts on lateral stiffness. Wonder what your next rims will be, would you put on round gauge spokes for the rear for increased lateral stiffness and cx-ray on front for aero? Yeah and roads in HK are harsh, replaced bearings in my rear hub after only 6000km. Just got a replacement for my Garmin, got a wahoo elemnt bolt like the rest of KZbin, any experience with it?

[@andreasboger8261]

Relating to your observation of the spoke nipples becoming loose over time: Are you aware of the influence of tire pressure on the spoke tension? In my last wheel build with quite similar rims to yours I’ve experienced, that the spoke tension lowered from 100 kgf to about 70 kgf after putting the tire on and inflating it up to 7 bar/100 psi. It was a tubeless setup on 25 mm deep Mavic-UST alloy rims with 19 mm inner width. I discovered this quite strong effect after my first wheel build a year ago. I tensioned the wheels without the tire on. On the ride the wheels felt quite wobbly and after the first 500 km I’ve found a totally loose spoke on the rear wheel and wondered why. Because of the cassette on the rear wheel, the tension ratio left to right hand is typically about 3/5, if the spoke count is the same on the left and right. My initial tension was 60/100 kgf. After inflating it could went down to 30/70 kgf. I actually observed some decentration, but I thought it was due to my bad truing. Months later I’ve got the Idea, that the tire pressure could actually compress the rim and therefore lower the spoke tension. On my second attempt I trued the wheel a second time with the tires beeng inflated to the desired riding pressure and the wheels are pretty stiff now. I’ve just done a quick calculation: inner width (without the hooks: 21 mm) x inner rim diameter (622 mm) x Pi x tire pressure (7 bar i.e. 0.7 N/mm2) / spoke count (in my case: 32) = 898 N per spoke or 92 kgf per spoke of increased rim tension The rim appears to take 2/3 of the load, handing over 1/3 to the spokes. In my opinion it’s plausible.

[@PeakTorque]

Andreas Boger Hi Andreas. Nice comments. Yes the tyre definitely affects the tension and it all depends on how stiff the rim is vertically. I true the wheels, then check the tension again with the tyre inflated. On deep section carbon wheels, I don't notice much difference because vertically the rim is very stiff and resists compression. In a shallow Alu rim the effect would be greater because the stiffness is lower. When you think about a tyre on a rim there are 3 stress compenents due to inflation pressure. Hoop stress, axial stress, and radial. Separating these and calculating them is almost impossible by hand as the rim/tyre system is not a simple pressure vessel. Hey, maybe I will do a video on it. Alu rim Vs carbon rim. What do you think? Also I would really recommend 120kgf in the drive side of your rear wheel. 100kgf sounds too low. Don't forget half the spokes de-tension as you apply torque.

[@andreasboger8261]

Cycgnr, yes I agree with you. Of course, my calculation is just a rough approximation to get an idea for the order of magnitude of the effect. And yes, it depends on the stiffness of the rim, but not only: actually, the rim and the spokes are like two pretensioned springs with in general different stiffness but the same deflection. Therefore, by applying additional loads the stiffer part takes more load, and the stiffer the spokes or the higher spoke count, the more will the spoke tension lower with the same rim. Furthermore, if there are hooks for the tire bead, the bead pulls slightly on the the rim in radial direction and reduces the effect. If there is an inner tube, it also reduces the effect by taking some of the load. The worst case scenario would be: tubeless, hookless, wide and shallow rim, high pressure and many thick spokes (in case you’ll do a video on that). The spoke holes in my rim are designed for loads up to 120 kgf or 1200 N, and I do exploit this limit on the drive side. Hence there is this cassette-given load-ratio of 3/5 for non-drive vs. drive side, for my next wheel build I consider an unequal spoke count of 1/2 for left/right to get a more even spoke-tension ration of 6/5. In fact, I’ve seen many of Shimano and Campagnolo wheel-sets being laced like this. The downside is though, that you are than limited to total spoke counts that are multiples of three. In practice you could choose a regular hub and rim with a spoke count of a multiple of four and use only every second spoke hole on the left side. The usual range of hole counts would be 36, 32, 28, 24 resulting in a total spoke count of 27, 24, 21 or 18, respectively. I think, it would be an effective way to get a fairly rigid but light wheel. The next thing, I have to think about, is the effect of this particular lacing pattern on the magnitude of dynamic loads due to rolling and paddling, since it determines the lifetime of the spokes. My intuition says me, that it should be also more even from left to right. As far as I know, for the “normal” lacing the dynamic load due to rolling is higher on the right side, for which reason the lifetime of the spokes is usually shorter there (the static pre-load is of course higher there too). I appreciate your reasonable approach. Most of the other cycling related channels are just marketing driven and without any reasoned opinion. So, keep it up!

[@cypriano8763]

my 2011 tcr bars just broke, from sweat corrosion. might want to have a look under the bar tape

[@wesw6787]

First time I hear someone complaining about the bb stiffness of a tcr... Which other bikes have you tried?

[@PeakTorque]

Wesley Wuyts its an xl frame and the tubes are small for that size. Supersix evo, cervelo s3, caad10/12, Orbea Orca omr. All feel stiffer in the same size in. Y opinion with the same wheelset.

[@adambolter4965]

@@PeakTorque whats your opinion on the orbea?

[@iaretehleet]

Would you say that your CAAD is a stiffer bike? You still own the CAAD right?

[@PeakTorque]

iaretehleet hard to tell. Vertically stiffer yes. The TCR is pretty squishy and comfortable. But laterally it's hard to tell as the bars are quite soft on the TCR making it feel a bit sloppy. When I get them together il do a proper stiffness test if I can rig it up.

[@arifazhari7598]

How many saddle to bar drop you need. Peak torque : yes

[@yakazoko3856]

Is that bike confortable on long distances ? What's your longer distance with this bike and you butt feeling at the end ? ^^

[@m4punisher25]

I’ve owned a 2016 tcr for 4 years now and I’ve clocked many 60-130 mile rides and it has sufficed, given you have the correct fit and saddle for your ass I rarely suffer from saddle sores

[@dickieblench5001]

Those wheels don't look strong enough for 90kg. Try Zondas they're strong AF

[@batbawls]

It sounds like the spokes weren't continuously detensioned and then retensioned properly during the wheel build, which is important unless you want to do a second and third round of tensioning and truing after it's been ridden a while and the spokes loosen a bit. Edit: I didn't realize you are 90kg, which I guess plays a bigger factor

[@PeakTorque]

Thurston Howell III i agree with your statement. However. They were fine for a good while after building. A year or so. This hub has a low NDS tension ratio of 45%. Under low rpm high torque scenarios (v steep climbs) it is easy for the trailing 2x NDS spokes to almost become completely de-tensioned where nipple slippage can occur. Added to the de-tensioning of the under hub spokes due to my fat arse and you have quite a situation! Cheers

[@PeakTorque]

Thurston Howell III if just talking about the front wheel I agree

[@paulysci925]

Very smart review 👍🙂

[@VisualKIt.Studios]

Very geeky review, i like

[@peternormann8959]

How tall are you?

[@PeakTorque]

1950mm