Pw50 Starts but will not turn rear wheel. Any advice please?

[tmm]

Hi

I have a Yamaha PW50 (2007/8 model) which starts up 1st time, the engine runs spot on but it will not engage the back wheel. The back wheel turn easily by hand so its not the brake sticking. Its been working great until the other day when i got it out for the bairn. Would love some feedback on what it could be.

Cheers.

[Tango]

I'm no expert on these things, but it sounds like the centrifugal clutch isn't engaging......so either something is stuck in there, or something is broken or worn out.....have a look at the parts and see if you can suss out what's happening. .....https://www.fowlersparts.co.uk/parts/5433737/pw50-2005-5pga-europe-deep-purplish-blue-solid-e/clutch

[Guest]

Hi

I have a Yamaha PW50 (2007/8 model) which starts up 1st time, the engine runs spot on but it will not engage the back wheel. The back wheel turn easily by hand so its not the brake sticking. Its been working great until the other day when i got it out for the bairn. Would love some feedback on what it could be.

Cheers.

 

Seems like its f**ked! You will somehow need to get it to a garage. Do you have breakdown cover with home start? If not buy some, wait a week or 2 then call them to get it taken to a motorcycle garage.

[fastbob]

Hi

I have a Yamaha PW50 (2007/8 model) which starts up 1st time, the engine runs spot on but it will not engage the back wheel. The back wheel turn easily by hand so its not the brake sticking. Its been working great until the other day when i got it out for the bairn. Would love some feedback on what it could be.

Cheers.

 

Seems like its f**ked! You will somehow need to get it to a garage. Do you have breakdown cover with home start? If not buy some, wait a week or 2 then call them to get it taken to a motorcycle garage.

 

That's not very helpful or funny . Not a very nice way to treat a new forum member seeking practical advice.

[TimR]

Hi

I have a Yamaha PW50 (2007/8 model) which starts up 1st time, the engine runs spot on but it will not engage the back wheel. The back wheel turn easily by hand so its not the brake sticking. Its been working great until the other day when i got it out for the bairn. Would love some feedback on what it could be.

Cheers.

 

Seems like its f**ked! You will somehow need to get it to a garage. Do you have breakdown cover with home start? If not buy some, wait a week or 2 then call them to get it taken to a motorcycle garage.

 

As its not a road legal vehicle don't waste your money on breakdown cover ... it won't be covered.

[TimR]

If this has a one way bearing in the clutch system ( a bearing that when it spins in one direction ( under engine power) it grips the shaft and drives the clutch and forward you go , but when not travelling in that direction ie being wheeled about backwards etc it just freely rotates )

These can dry out over time and can require a bit of lubrication to work properly .

If you can find a owners manual / maintenance schedule see what is required to maintain etc

[fastbob]

Right then , I think you can see the bad news AND the good news in one screenshot. Only trouble with second hand is there's a chance its also knackered but worth a go

[Via]

I'd pull apart current one first and give it a good clean down, if corrosion set in and arms stuck they will never spin out and engage.

[fastbob]

I'd pull apart current one first and give it a good clean down, if corrosion set in and arms stuck they will never spin out and engage.

 

Good point .

[fastbob]

If this has a one way bearing in the clutch system ( a bearing that when it spins in one direction ( under engine power) it grips the shaft and drives the clutch and forward you go , but when not travelling in that direction ie being wheeled about backwards etc it just freely rotates )

These can dry out over time and can require a bit of lubrication to work properly .

If you can find a owners manual / maintenance schedule see what is required to maintain etc

It's actually got a centrifugal clutch that looks not unlike a drum brake assembly. Bob weights fly outwards upon rotation and friction pads engage with the outer drum , twist and go in other words. See pictures In my other post.

[tmm]

Cheers everyone for the advice and fast replys. I will start looking as suggested and keep you posted on what i find.

[tmm]

Hi

I have a Yamaha PW50 (2007/8 model) which starts up 1st time, the engine runs spot on but it will not engage the back wheel. The back wheel turn easily by hand so its not the brake sticking. Its been working great until the other day when i got it out for the bairn. Would love some feedback on what it could be.

Cheers.

 

Seems like its f**ked! You will somehow need to get it to a garage. Do you have breakdown cover with home start? If not buy some, wait a week or 2 then call them to get it taken to a motorcycle garage.

 

That's not very helpful or funny . Not a very nice way to treat a new forum member seeking practical advice.

 

Its fine fastbob life is full of Morazons I can cope with people like that but other new members may not and just leave the forum.

[tmm]

I'm no expert on these things, but it sounds like the centrifugal clutch isn't engaging......so either something is stuck in there, or something is broken or worn out.....have a look at the parts and see if you can suss out what's happening. .....https://www.fowlersparts.co.uk/parts/5433737/pw50-2005-5pga-europe-deep-purplish-blue-solid-e/clutch

 

Cheers Tango for the parts list

[Guest]

Hi

I have a Yamaha PW50 (2007/8 model) which starts up 1st time, the engine runs spot on but it will not engage the back wheel. The back wheel turn easily by hand so its not the brake sticking. Its been working great until the other day when i got it out for the bairn. Would love some feedback on what it could be.

Cheers.

 

Seems like its f**ked! You will somehow need to get it to a garage. Do you have breakdown cover with home start? If not buy some, wait a week or 2 then call them to get it taken to a motorcycle garage.

 

That's not very helpful or funny . Not a very nice way to treat a new forum member seeking practical advice.

 

I was trying to give him advice, not put him down in any way. Hardly what I would call "not a very nice" way to treat someone, even if you may not agree with my advice.

 

Hi

I have a Yamaha PW50 (2007/8 model) which starts up 1st time, the engine runs spot on but it will not engage the back wheel. The back wheel turn easily by hand so its not the brake sticking. Its been working great until the other day when i got it out for the bairn. Would love some feedback on what it could be.

Cheers.

 

Seems like its f**ked! You will somehow need to get it to a garage. Do you have breakdown cover with home start? If not buy some, wait a week or 2 then call them to get it taken to a motorcycle garage.

 

As its not a road legal vehicle don't waste your money on breakdown cover ... it won't be covered.

 

I didnt know that. I took it for granted that he was a learner or something having trouble with a general 50cc Yamaha road motorcycle.

[fastbob]

Apology accepted ,Id rather not kiss your bottom and I'm definitely keeping my jumper on in this weather.

[Jamievale]

On 26/02/2018 at 20:17, tmm said:

Cheers everyone for the advice and fast replys. I will start looking as suggested and keep you posted on what i find.

Did you get this fixed? Having same problem with mine but it grabs and will turn just not consistently 

[Tinkicker]

On 26/02/2018 at 07:53, Guest said:

 

Seems like its f**ked! You will somehow need to get it to a garage. Do you have breakdown cover with home start? If not buy some, wait a week or 2 then call them to get it taken to a motorcycle garage.

 

Very knowledgeable reply.  It is always good to get advice from someone that does not know a PW50 from a slice of mouldy cheese.

 

To the OP.  First things first.  Did you remember to move the ignition switch from the start position to the run position once it was running?

 

It is over 15 years since I worked on a PDub but if memory recalls, there is a centrifugal clutch on the right side of the engine.  If the weights and therefor the clutch friction surfaces are stuck or there are other problems within the drum, it may not engage.  This clutch drives a cross shaft with a bevel gear on the end, which takes power to the left side of the bike.  The power is then transmitted through 90 degrees via a bevel gear set on the front end of the driveshaft.  If the teeth are stripped on either of these, they will not transmit power down the driveshaft.

 

At the rear end of the driveshaft you have a crownwheel and pinion setup which once again turns the power through 90 degrees and feeds the power to the rear wheel through a set of splines within the wheel hub.  Any damage or wear to any splines, teeth or bearings within the system of shafts and gears will prevent power from reaching the back wheel.

 

Edit.  BTW.  The crownwheel and pinion are lubricated by grease, not oil.  Always ensure there is plenty of grease packed into the rear housing.

 

First point of call is the clutch.  You can check if power is going through the shafts to the wheel from there.

 

 

 

 

Edited March 19, 2023 by Tinkicker