Technical help for Series one, two and three Lambrettas. Models include the Li, Li Special, TV, SX, GP, Serveta and API/SIL models
by Paullr » Sat Nov 22, 2014 8:08 am
Hi all
posted this q on the sip forum but no answers even from sip
the video guide to fitting tyre says 40lb, guess thats to get the tyre sat on the bead properly , should we run at that pressure or drop to normal split rim pressure
Paul
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Paullr
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by Digger » Sat Nov 22, 2014 8:34 am
Yes. (JIMHO). 40 would be ok on a salt flat.
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by bob » Sat Nov 22, 2014 7:03 pm
Was advised to run mine about 10psi higher than I would on standard split rims, have done this for the last couple of years and so far they seem fine
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by Digger » Sat Nov 22, 2014 9:52 pm
bob wrote:Was advised to run mine about 10psi higher than I would on standard split rims, have done this for the last couple of years and so far they seem fine
Who by?
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Digger
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by bob » Sat Nov 22, 2014 10:03 pm
The guys at MB where I get my wheels/tyres from
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by CHRIS in MARGATE » Sat Nov 22, 2014 10:08 pm
And on what evidence do they base that information ?
Wrong info I say !
PSI is PSI whatever the tyre or rim.
Take it to 40 + to get it to go seal on the bead and then deflate to correct PSI.
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CHRIS in MARGATE
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by bob » Sat Nov 22, 2014 10:32 pm
From what I can remember it was based on the modern profile/compound tyres fitted to tubeless rims are more suited to higher pressures, but hey wtf do I know, can only go on what was recommended, and as I said earlier, no complaints with performance or tyre wear over the last two years
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by Simon ELC » Sat Nov 22, 2014 10:58 pm
CHRIS in MARGATE wrote:And on what evidence do they base that information ?
Wrong info I say !
PSI is PSI whatever the tyre or rim.
Take it to 40 + to get it to go seal on the bead and then deflate to correct PSI.
What's the correct PSi? The one that's stated in a 1950/60 owners manual for a ditch finder or the maximum quoted on a modern tyre?
An underinflated rear tyre will create heat and let go when you least need it. keep the pressure up.
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by Digger » Sun Nov 23, 2014 6:26 am
I quite agree about the low pressure Simon but 40 PSI is somewhat high.
40 PSI around my local roads and you may as well have a solid rubber tyre.
I've always gone 20/30 since the first time I had cause to put air in a 10" tyre.
Road, race, tubed or tubeless.
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Digger
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by CHRIS in MARGATE » Sun Nov 23, 2014 10:15 am
Please do not pump the tyres up on 2 wheels or 4 to the maximum the tyre can take. Please don't construe my take on this as an argument for the sake of an argument but over- inflation, more so on the front will have seriously dangerous implications with regard to steering. Have you driven a car with over inflated front tyres ? Terrifying !
Try it if you don't believe me. No DON'T.
40psi is a figure "plucked out of the sky"
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by a-teamlambretta » Sun Nov 23, 2014 10:34 am
So what pressure is recommended for a modern twist and go fitted with a similar size tubeless tyre??, I would have thought higher than the recommended for a standard tube and split rim of 50 odd year old design ???. I agree with the over inflation to get them seated on the beed. I could be wrong though lol
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by Digger » Sun Nov 23, 2014 12:12 pm
26/29 for a GTS 32 with a pillion.
Slightly bigger tyre of course.
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by a-teamlambretta » Sun Nov 23, 2014 1:19 pm
malaguti f10 with 100/80-10 , f 29psi/ r 33psi
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by Paullr » Thu Nov 27, 2014 9:03 pm
Thank for replies
i guess a good indication is the modern scooter reccomendations
Paul
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by 69GP225 » Tue Jul 14, 2020 10:10 pm
Had a bit of a scare tonight, finally got GP back together but thought my brake was on a little. Bike seemed hard to push.
Released brake adjustment a little And took for a spin. Got half way down the road and bike snaked. Tubeless tyre had come of rim?
So my thought is the tyre had lost pressure reason why the bike seemed hard to push and didn’t notice the tyre. So my question is why would a tubeless tyre goes down on a hardly worn tyre which is on a brand new rim?
Yes it’s definitely a tubeless k62 Heideneu tyre designed for these rims. I haven’t seen a tubeless Sip rim lose pressure yet so it’s a first. Could it be that not much pressure had been pumped to seal it and movement of the bike and weight and impacted the integrity of the bead?
Or maybe the valve?
Anyone had a similar thing happen?
No damage done and shit my pants ha.... ha
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by missing lynx » Tue Jul 14, 2020 10:15 pm
I run mine 20psi front 34 psi unloaded 38psi load on the back check the valve on one of my sip rims the valve didn't seat properly
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by 69GP225 » Tue Jul 14, 2020 10:46 pm
Thanks mate, that was my thought the valve.
Sorry they were k61 tyres
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by rossclark » Wed Jul 15, 2020 12:19 am
I usually run 20 / 30
I have one now City Grip Winter that won't hold pressure but not had a chance to really investigate why yet
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by CHRIS in MARGATE » Wed Jul 15, 2020 8:51 am
Wow... old post. I run Michelin City Winter Gtips on AF Tubeless. No pressure loss but I know others that have.
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CHRIS in MARGATE
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by 69GP225 » Wed Jul 15, 2020 9:28 am
Yep always good to resurrect a good post. Thanks for all your comments and going to try a new valve.
Thanks Lee
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