Grand Prix 5000TL for Giant SLR 1 Areo 42/65 mm?

You don't usually need a different tube for 28mm, an 18-25mm tube will just be a tiny bit thinner as it stretches to fit the slightly larger volume.

If you don't believe me try putting some air in a spare tube and see how big it gets.

I've tried Stans, Conti Revo, Bontrager and Orange Seal. Bontrager is the one which works for me best. Stans was the worst, just useless at high pressures, I just feel like I've done enough guinea pig testing for me not to want to 'risk' using their newer race version, Bontrager works great and goes through the valve, you just need to shake the hell out of the bottle every time you top up.

Don't use stans sealant. I prefer the Bontrager sealant it just works best at higher pressures.

You don't need 40ml sealant, I use 25ml with no problems. 

25mm tyres would be normal, I use Schwalbe Pro Ones and can't justify swapping to another brand, I've looked at the Conti's and the rolling resistance is tempting, but the additional weight is offputting, on balance I might try a set next time I need to change tyres but I can't see it making much difference. I've got nothing but good things to say about the Schwalbes, I've gone through about eight tyres since I started running tubeless in 2015. 

Buy the better size for your purpose and do some riding. When you need to replace them then you can consider whether to buy the same again or a different tyre.

I wouldn't sweat over the details - 40g weight difference or the aerodynamics of 25mm v 28mm - as any claimed differences will be so tiny as to be undetectable in the real world.

Hi. I’ve recently bought the new GP5000 TL tyres for both my bikes. I used to use Shwalbe pro one tyres but they were very delicate and didn’t last very long so I went back to clinchers. Now Continental have released a tubeless tyre that’s similar to the old GP4000 I have gone back to tubeless. 

Fitting the GP5000’s was quite easy on my aluminium wheels but difficult on my Bontrager carbon wheels (really really difficult to get on the rim). Both sets of tyres pumped up very easily with my cheap and not very good track pump. 

So far I’ve ridden over 350 miles on them. They feel better than clinchers but dont don’t feel as good as the Shwalbe pro ones, maybe less supple, but if they are as puncture resistant, long lasting and reliable as the GP4000’s while offering me the benefits of tubeless I’ll be very happy. I can’t really comment on the weight as I don’t weigh my tyres and I’ll happily carry a few more grams for a better all round tyre otherwise I’d still be riding Shwalbe Pro One’s.

Ive no idea which sealant is better. I use Stans but whenever I had a puncture with Shwalbe Pro One’s it’s because a small flint got stuck in the tyre and it wouldn’t seal until I removed the flint by which time all the air was gone to the tyre wouldn’t seal anyway.