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I dont know if its normal for the PKs to have a hot rear tyre and rim after riding.
The tyre you can just touch but its really hot.
I ask if its normal because the exhaust pipe header on this model is only a cm or so away from the rear tyre?
Ive checked the wheel for brake rubbing and other issues but have so far found nothing...
But all the same its got me worried...
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Rear brake is rubbing on the drum.
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Redirect the exhaust down.
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UTC quote
Is it just the tyre and rim or is the hub hot as well?
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SubEtherBASS wrote:
Rear brake is rubbing on the drum.
Unfortunately its not..
It would be good if it was then I would loosen the rear brakes off..
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Championstuff wrote:
Redirect the exhaust down.
You mean cut the pipe?
This wont work as the mounting of the exhaust is welded to body of the exhaust....unfortunately..
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Ginch wrote:
Is it just the tyre and rim or is the hub hot as well?
the hub is also warm, but not as hot as the tyre and rim..
Im thinking perhaps the heat is passing from the Tyre/Rim to the hub as both are being heated up by the exhaust...well thats what I think

I will take another look today at it,..
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Robbie 11 wrote:
Championstuff wrote:
Redirect the exhaust down.
You mean cut the pipe?
This wont work as the mounting of the exhaust is welded to body of the exhaust....unfortunately..
I heard a trick where you can insert a small 90 degree elbow of copper tubing into the exhaust tip and that will redirect your exhaust to point down. It will also help from blowing all the engine crap all over your wheel and hub
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Under-inflated tires could get hotter than normal. Just sayin'...I suppose you've checked the tire pressure. 8)
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What about a misaligned tire/wheel on the back, due to bad mounts or bent shock? I know it'll affect the handling (which you'd probably notice) but it will also cause the tire to rub more on the pavement as you go down the street, causing more heat?

Dumb ass guess....
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JKJ-FZ6 wrote:
Under-inflated tires could get hotter than normal. Just sayin'...I suppose you've checked the tire pressure. 8)
This.
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Do this to check the brake...
Put something under the engine or frame to hold the wheel off the ground and give the wheel a spin while repeatedly applying and releasing the rear brake. It should spin free with no brake, stop when braked, and spin free again when released.

Or... is the tire rubbing on the clutch cover? This could be caused by worn or misaligned parts, or improper inflation.

If it's the brake, you have an annoyance that will prematurely wear out your shoes and not function well.

But if it's friction, either from rubbing on something or from improper inflation, then it's dangerous and will likely end in a rear wheel blowout, something every moto rider doesn't like to think about.

Dumb question...
It's not the ambient temp of the pavement, is it?
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pdxjim wrote:
It's not the ambient temp of the pavement, is it?
You could check that by comparing the temp of the front tyre.

We still haven't heard what pressure is being run in this tyre.
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^^^
If the rider is heavy, it's possible that standard tire pressure isn't enough.
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Tyre pressure is 2.5 on the rear which is what they recommend for this model.
The tyre size is 90/90 x 10 so shouldnt be to wide.
Im only 70KG around 11.3 stone so not a heavy bloke

Ive been busy with work the last couple of days so I havent had much time to look further.
I will have a look today and take some photos.
I will also jack the bike up on axle stands and check for any rubbing.

Cheers
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36 psi, so under-inflation won't be the issue.
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So I put the body up on stands so that the rear wheel was of the ground.
There was no rubbing or resistance of any sort.
If I spin the wheel once with my hand it will keep turning for 5 to 6 turns by it self.
I took the wheel of and checked both the tire and rim for rubbing.
No signs of any rubbing.
Also checked the exhaust pipe and clutch cover, rear shock and the motor for any rubbing marks. Nothing..
Checked the tire pressure again and the pressure is correct at 2.5.

But if you see the attached pic you can see that the exhaust pipe is bloody close to the rear tyre.. Is this normal?
Anyone else got a PK with the same close fit..
The tire is a 3.00X10 SIP Performer Tire so shouldnt be too wide.
https://www.sip-scootershop.com/en/products/tyre+sip+performer+_79790000
Picture of rear tire and exhaust pipe
Picture of rear tire and exhaust pipe
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FWIW I measured the temperature of the tires on my Zuma (12 inch wheels) with an infrared thermometer after a 20 mile, 45 mph ride to work. The rear was 93F (38C) and not really hot to the touch. The front was 76F (27-28C).

If you can't attribute your tire's heating to the exhaust or something else, I suggest there may be a defect in the tire (like delamination maybe?) and it should be replaced ASAP.
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JKJ-FZ6 wrote:
FWIW I measured the temperature of the tires on my Zuma (12 inch wheels) with an infrared thermometer after a 20 mile, 45 mph ride to work. The rear was 93F (38C) and not really hot to the touch. The front was 76F (27-28C).

If you can't attribute your tire's heating to the exhaust or something else, I suggest there may be a defect in the tire (like delamination maybe?) and it should be replaced ASAP.
Thanks for the info really appreciated, the tire is new..
My feeling is that all PKs have a similar problem to the one Im experiencing..
But please correct me if Im wrong (Fellow PK owners)
How can Piagio design a motor with the exhaust pipe so close to the rear tire?
Perhaps Im being a pussy and I should ignore this for what seems to me an extremely hot rear tire.. But with all due respect to Piaggio the pipe so close to the rear wheel seems a little crazy??
Anyone with a PK with similar experience?

It could also be that the tire only heats up as soon as I stop and the direct heat from the exhaust header is like a toaster for the tire..

I wouldnt worry if it was me riding this on long trips but its the wife, and Im sure she would lose it if the rear tire exploded on the highway or in a corner..
Just got me a little concerned..

Thanks for all the tips and sorry for the pessimism
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Lots more PK riders on the smallframe proboards forum, and they are particularly knowledgeable. If you want some more info I'd post up there, I always get good technical smallframe answers from that forum.
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sdjohn wrote:
Lots more PK riders on the smallframe proboards forum, and they are particularly knowledgeable. If you want some more info I'd post up there, I always get good technical smallframe answers from that forum.
Makes sense..Will Do thanks...

Thanks to everyone for the tips and advice..

Cheers
Robbie
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