ETZ 251 little bit noisy clutch ?

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ETZ 251 little bit noisy clutch ?

Postby alexxx » Wed Apr 05, 2017 3:52 pm

Hi Folks,

You can tell I just got anew MZ ETZ 251 by all the questions I ask on this forum.
Anyway, the bike was unused by the previous for at least a year and amazingly it started on the 3rd kick, while listening to it running, all sounded quiet then I pulled in the clutch lever and it became really quiet, let the clutch out and bit more noisy.
Sounds like the clutch has a small rattling noise, not much but you notice the engine is quieter with the clutch pulled in, this may be normal ?
If it was a car I would say..clutch thrust bearing (quieter when clutch pedal is pushed down) should I be concerned about this or is it standard MZ?
Thanks
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Re: ETZ 251 little bit noisy clutch ?

Postby Blurredman » Thu Apr 06, 2017 6:27 am

My clutch is very noisy. Unfortunately the crank end is completely mashed up by a previous owner so I can't even get the clutch off (I sincerely hope I don't have to take the engine apart..)

From my experience with these types of clutches, yes they are noisy, it's a typical single bearing being pushed against when the lever is pulled. The bearing is very large though compared to the size of the thrust bearing in say a Honda CX500. How many miles on the engine? Mine has 31k miles now and is definately a clutch rattler, but sweet otherwise. I've noticed with these bikes in particular that even when warm, there is a clutch drag, and for my bike this reduces engine RPM by 200rpm. I am using 20w/50 oil though, which is a secondary recommendation according to the official manual. SAE80 is the recommended for best use (GL3/GL4-Not GL5!!) But I doubt that would have any effect on the noise of the engine.


But in short, yes it is normal, infact a hell of a lot of bikes (and even my car!!) has clutch rattle for whatever reason, because the thrust washer is just barely being touched, to the basket being not quite centred, or the wear of the plate teeth against the basket. You'res, like mine will likely be either the washer or indeed the lever rattling against the bearing.
1972 MZ ES250/2 - 16,000 miles - The project! :)
1979 Suzuki TS185ER - 9,000 miles - Mud :)
1981 Honda CX500B - 91,000 miles - Long Distance :)
1987 MZ ETZ300 - 38,000 miles - Sun :)
1990 MZ ETZ251 - 49,000 miles - Commute :)

ftp://blurredmanswebsite.ddns.net/Vehicle_Documents/MZ_Documents/
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Re: ETZ 251 little bit noisy clutch ?

Postby alexxx » Thu Apr 06, 2017 7:37 am

Thanks Blurredman,

So it is a thrust bearing, fine I can live with that until I need to remove the case for any reason, hopefully my crank will be good and not mashed.
Not sure about my bike's miles, speedo larger letters are in KM with miles in the minor so I assume the 66,000 is km? so maybe 41,000 miles, high either way.
No idea of the service history, have to assume zero.
Thanks for the oil info, I will change it this weekend.
What can you do if ever you need to remove your clutch?
alexxx
 
Posts: 120
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Location: Edinburgh Scotland

Re: ETZ 251 little bit noisy clutch ?

Postby Blurredman » Fri Apr 07, 2017 5:13 am

As mentioned on the other thread, those clocks are replacement.
I would advise using the MOT history service on the GOV website to see what previous MOT's the clocks are showing..


Remember.. GL3/4 oil. NOT GL5! I made that mistake one, the clutch plates fused together.. Was fine after a flush.


I think i'd have to grind the end of the crank to give a flat surface and try again. That's all I could do.
1972 MZ ES250/2 - 16,000 miles - The project! :)
1979 Suzuki TS185ER - 9,000 miles - Mud :)
1981 Honda CX500B - 91,000 miles - Long Distance :)
1987 MZ ETZ300 - 38,000 miles - Sun :)
1990 MZ ETZ251 - 49,000 miles - Commute :)

ftp://blurredmanswebsite.ddns.net/Vehicle_Documents/MZ_Documents/
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Location: South Wales

Re: ETZ 251 little bit noisy clutch ?

Postby Skorpion » Fri Apr 07, 2017 11:10 am

Silkolene light gear oil has been the recommended oil by riders for a few years now.

http://www.ebay.co.uk/itm/SILKOLENE-MOT ... SwHaBWi9~5

Helps the gear change & sticking clutch plate problems.
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Re: ETZ 251 little bit noisy clutch ?

Postby alexxx » Thu Apr 13, 2017 9:43 am

Thanks All :)
alexxx
 
Posts: 120
Joined: Sat Mar 04, 2017 8:06 am
Location: Edinburgh Scotland


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