Changing tyre sizes...

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slowster
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Re: Changing tyre sizes...

Post by slowster »

TheNissanMan wrote:Im Still debating the sun cream, after numerous years overseas I tend to be ok in the sun for very long the UK once I have my base coat which I’ve already built up :) may use some on neck and face.

Glasses, I swear by polarised Oakley as used to do a lot of miles on the road (40-50k a year) and they are the only glasses I find suitBle from rain to sun...

Am tempted to buy a cap but concerned that I over heat quickly and a cap would get very hot? May be useful if it rains though? Thinking it could keep,rain out of eyes ?

Ignore my comment about a baseball cap - I forgot you'll doubtless be wearing/required to wear a helmet on an organised event like L2B. I don't always wear a helmet, and I often take a baseball cap and put it on for part of the ride (usually taking it off when riding uphill and sweating, or riding in shade).
You might find that an old fashioned cheap cotton cycle cap would be good underneath the helmet in the rain, because the peak does a good job of keeping rain out of the eyes.
TheNissanMan
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Re: Changing tyre sizes...

Post by TheNissanMan »

Unfortunately are forced to wear a helmet for l2b although two design if it can be removed once we’ll clear of the start lol.

I do have mits, some cheap ones from Aldi but do the job well and much more comfortable than barehand and take on board the comment about falling, tired legs, lots of cyclists and a long day, I’m sure there will be Shimano moment at some point!

I’ve been reading the reviews on the Vittori tyres I’ve ordered, I know pressures were mentioned early and thinking out loud, would it be easier (albeit higher risk of punctures) to inflate the tyres closer to max? Earlier recommendations were circa 45psi front, 65 rear so a couple of questions (sorry)...

Would 85 at the rear again mean easier going and why lower the pressure on the front, I can understand it in a car to change over/under steer and grip but on a bike can’t see it making the same difference?
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Re: Changing tyre sizes...

Post by TheNissanMan »

Ignore that bit on pressures... just found the answer on this forum!!! Although still don’t understand why differing f/r pressures.
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foxyrider
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Re: Changing tyre sizes...

Post by foxyrider »

TheNissanMan wrote:Ignore that bit on pressures... just found the answer on this forum!!! Although still don’t understand why differing f/r pressures.


TBH most people pump them up the same so you aren't alone!

To put it simply, a bit of extra air in the rear compared to the front helps compensate for the extra weight the rear wheel carries. How much extra is one of those imponderables. It's not a simple thing to work out, more air should lessen the incidence of punctures (not increase) and heavier riders should put more air in too.

At 87kg I generally run the rear tyre @ 10psi higher than the front regardless of tyre size.
Convention? what's that then?
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TheNissanMan
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Re: Changing tyre sizes...

Post by TheNissanMan »

Sorry to be asking again, after looking at Vittorias website, 5eir tyr epressure calculator factoring in my weight (17st) suggest 115psi front and 120 psi rear which sounds , does that really sound right ?
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foxyrider
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Re: Changing tyre sizes...

Post by foxyrider »

TheNissanMan wrote:Sorry to be asking again, after looking at Vittorias website, 5eir tyr epressure calculator factoring in my weight (17st) suggest 115psi front and 120 psi rear which sounds , does that really sound right ?

Sounds maybe a bit high unless you ordered 23 or 25c size. Would have expected more like 85/90 with 38c.
Convention? what's that then?
Airnimal Chameleon touring, Orbit Pro hack, Orbit Photon audax, Focus Mares AX tour, Peugeot Carbon sportive, Owen Blower vintage race - all running Tulio's finest!
hodge
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Re: Changing tyre sizes...

Post by hodge »

TheNissanMan wrote:Sorry to be asking again, after looking at Vittorias website, 5eir tyr epressure calculator factoring in my weight (17st) suggest 115psi front and 120 psi rear which sounds , does that really sound right ?


Frank Berto's table isn't a bad place to start from, then fine tune it yourself bearing in mind your tyres may be more or less supple than those he based the test on:

http://www.chirundu.com/wp-content/uplo ... lation.pdf
reohn2
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Re: Changing tyre sizes...

Post by reohn2 »

TheNissanMan wrote:Sorry to be asking again, after looking at Vittorias website, 5eir tyr epressure calculator factoring in my weight (17st) suggest 115psi front and 120 psi rear which sounds , does that really sound right ?

Youre waayyy off for 38mm Hypers I reckon at that weight and with the weight of the bike added,optimum tyre pressured would be around 55 to 60psi front and 70 to 75psi rear.
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TheNissanMan
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Re: Changing tyre sizes...

Post by TheNissanMan »

Thanks again guys, the chart provided shows a lot closer to where expected (and previously mentioned).
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horizon
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Re: Changing tyre sizes...

Post by horizon »

reohn2 wrote:These will enhance the ride quality and roll very well indeed :- https://www.planetx.co.uk/i/q/TYVIVOHY/ ... lding-tyre


I'm not doubting your choice of tyre but I'm wondering what difference it will really make for the OP? As I see it, this is a challenging ride for him and for which he is preparing diligently (that's not meant to be patronising). But for someone in the OP's position, more riding is the best preparation and better tyres might just be a false hope. I'm not questioning the idea of better (faster) tyres in general, just this person on this ride.
When the pestilence strikes from the East, go far and breathe the cold air deeply. Ignore the sage, stay not indoors. Ho Ri Zon 12th Century Chinese philosopher
TheNissanMan
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Re: Changing tyre sizes...

Post by TheNissanMan »

Not taken as a patronising comment at all, I know I’m a fat sod butworking on it, putting in the time in the saddle is the bit in my control.

Luckily have a reasonable job which allows me a bit of spare cash and options which make a tad more pleasurable and anything that can make it easier can only help.
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horizon
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Re: Changing tyre sizes...

Post by horizon »

TheNissanMan wrote:
options which make a tad more pleasurable and anything that can make it easier can only help.


100% to that - it's a good strategy :D (as will cake stops on the way be). BTW I've enjoyed following your progress through your preparation, one logical step after another. It will be really interesting to see how it all turns out, what worked, what didn't and what you would have done differently.
When the pestilence strikes from the East, go far and breathe the cold air deeply. Ignore the sage, stay not indoors. Ho Ri Zon 12th Century Chinese philosopher
Tangled Metal
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Re: Changing tyre sizes...

Post by Tangled Metal »

Monday night I finally got around to taking my planetx areo CX tyres my London road came with off and replaced them with 32mm hypers. I only had the CX tyres on because autumn I went off road and couldn't be bothered changing them back after winter.

I knew they were faster but didn't remember them being more than a minute faster on the half hour commute. On Monday I finally got sick of it feeling a struggle riding to and from work so I changed them back to the hypers.

What an improvement! I felt faster, I felt it was easier to ride and I was over 4 minutes faster. The easier to ride but intrigued me most. I've been struggling to get on top of the gears. By that I mean on my usual gear range I use for my commute I could only maintain a low cadence. Now I do mash it up a hill I don't on rolling or flatter sections. Over the winter I'd been only able to get on top of my gears downhill or if in the lowest of my usual gears. Second biggest cog on my 12t to 32t cassette on a 50t chainring.

With one ride on hypers again I read on top of the higher gears on the flat or rolling terrain. Second ride home I even got a 3rd best time on a strava segment and only 4s slower than my best time. I've not had a pb, second or third best time since last summer and this segment I've been at about 10+ seconds slower for at least two years! On a minute ten segment time for me that's a good time saving that can only be due to the tyre because I felt no better or worse than the day before.

So IMHO hypers are a good, fast tyre. I'm enjoying my commute again!

One thing I reckon makes a difference, mitts that work for you. By this I mean mitts that fit you well and has the padding that suits your in the places you need them.

For example, I broke my hand at the knuckle. For a while cycling was too painful. So I decided to look for mitts. I spent quite some time shopping around. Every place I went to with a bike shop got a visit to check out their mitts. I found a really good fit with padding that actually extended around the inside of my hand and around the side of my index finger knuckle joint that got broken. That meant the sore and aching part got nice, gel padding. Specialized mitts and top of their range I think too. Worth the extra money.
TheNissanMan
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Re: Changing tyre sizes...

Post by TheNissanMan »

Thanks for adding the comments, can’t wait to get them on the bike now!

I may have been lucky with mits, the first set I bought were some cheapies from Halfords to see what they were like and they were OK, not great. A friend who does a lot of exercise (Iron Man bits) suggested I got a muscle roller from Aldi so while buying it (not used it yet) I saw some cheap gloves and thought I would give them a punt as again a couple of pounds, they are so much better than the Halfords ones which have been binned. The padding is a lot better and a lot more comfortable.

Great to hear about your times coming down over your commute and can’t wait to see my times on known roads to see the difference.

They’ve been shipped so should be on the bike by the end of the week! Work are trying to get me on Sunday which I’m hoping to avoid as want a decent ride it on Sunday and Tuesday as my last full days off before the event and don’t want to do a long ride on the Saturday before the ride, a short 7-10 mile circuit planned for the Saturday early in the morning and then prep for an early start on Sunday.

The bike is having a service on Tuesday as well as the ride to check its as good as can be so by the end of play Saturday I want the water bottles lined up with powder so Sunday morning can just fill and go, only thing I haven’t tried before the event is the Sis Carb powders which will be taken in sachets in the pannier to have something in the water bottles for later in the day. Have tried other SiS products so should be OK. Again anything that may help will be tried...

Will post the Wahoo and Relive links once completed although may wait until the Monday as plan on doing very little bar either a walk or short ride depending on how I feel.
reohn2
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Re: Changing tyre sizes...

Post by reohn2 »

TheNissanMan wrote:Ignore that bit on pressures... just found the answer on this forum!!! Although still don’t understand why differing f/r pressures.

I missed this post.
The reason for differing front and rear pressures equate to weight distribution.
All but a racing crouch position(such as Foxy's)generally weight distrution is around a 40%front to 60%rear tyre pressures should reflect that.
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