Gearbox Issues

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Gearbox Issues

Postby suzukix7 » Thu Mar 19, 2015 11:12 am

Hi guys, just ridden my TS150 café racer for the first time to the MOT station where I'm glad to say it passed.
However, the bike keeps jumping out of gear! It seems to engage ok but jumps out every so often in most gears.
The bike has only done 5k from new with 2 previous owners. A bit surprised that the gearbox would wear so quickly?
Could it be something more simple than worn pinions or selector forks to save me having to strip it down?
If I do have to strip it, what special tools would I need if I'm just going to service the gearbox?
I've never stripped an MZ before but done Suzuki x7's a couple of times.

Many thanks
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Re: Gearbox Issues

Postby Agronski » Thu Mar 19, 2015 5:49 pm

First things first - make sure it's _actually_ jumping out of gear, and not just missing engagement. Let me guess - finding 1st gear is fine from neutral, but moving in to second gear it sometimes doesn't bite? The TS gearbox is too stupid to know better, you have to really haul up on the shifter to get it to engage fully.

Next, check your chain tension - if it's loose that can put an uneven load on the gearbox which won't help. Bit of a pain checking on the TS because of the gaiters - but there are ways to do it.

Thirdly, check your clutch adjustment. You are probably running original plates, so make sure the adjuster screw (under the right-side nacelle by the points/dynamo) is almost at the tension point when you lock the nut down. The manual says "back off 3/4 of a turn" - but that's when new. The clutch-springs will have lost a little tension over the years. Just nearly flush works well with my TS. Don't forget the cable adjuster on the lever, either.

Proper weight gear oil and the right volume is essential - too much and the clutch will struggle, too heavy a grade and the clutch plates will drag, even when completely disengaged. Too much oil in the case also puts a strain on the gearbox because the gears have to move more oil out of the way.

Finally, if all of the above doesn't solve the problem, you'll have to crack the case (special tools and/or Big Hammer essential) and check the selector lever, return spring, windows in the retainer plate and the selector dog. Sounds like a lot, but the actual gearbox is very simple. Probably it's just a worn dog, if it's even anything. Attached is the TS150 manual which covers it all - much better than Haynes, too.

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Re: Gearbox Issues

Postby suzukix7 » Fri Mar 20, 2015 7:40 am

Many thanks my friend for such a detailed and informative reply.
I will check all the points that you have mentioned before splitting the cases.
My clutch is definately not operating properly as it is dragging quite badly. I put it down to the fact that the bike hasn't been on the road since 1985!!! and figured the plates must be gummed together. I haven't used the correct weight of oil either!!
The gears do engage positively but yes 1st to 2nd is a problem but it doesn't like 3rd on occasion either and has jumped out whilst riding. The chain is new and of correct tension as I'm only running the chain case and not the gaitors (café racer)
I will drain the oil and use the correct oil and check the plates and springs for wear or contamination. I will then ensure the clutch is adjusted the same as you have advised. I will then run it for a while as I have only ridden it to the MOT station and back. I was gutted to be honest because I have been working on it since last June but never ridden it as it wasn't road legal. I was really impressed with how it rode (except for the gearbox!) Obviously if it doesn't need stripping then great. If it does though then many thanks for the manual as the Haynes one I have is very poor indeed.

Once again thanks for the reply

Dave
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Re: Gearbox Issues

Postby DAVID THOMPSON » Fri Mar 20, 2015 10:16 pm

pitch the haynes little book in the trash bin where it belongs..

this is a problem i had on a yamaha years ago...
bike yamaha ym1 1966

adjust clutch/ having trouble shifting
when it will shift proper at slow speed ok it then slips at high speed

when adjusted so no slip at speed then its hard to get in and out of neutral at slow speed 1st and second gear

sorted out that the hand lever was not pulling the cable a full stroke after bending the lever back
from the bar it started working.. lever was striking the bar before clutch released
may be or maybe not cause of your problem the lever was bent from a minor lay down of the bike
DAVE
i think i have posted on this before here on this site and i have found this on 3 different bikes over the years
Dave 2002 MZ RT125+1995 Saxon Tour(500cc)
1997 MZ 660 Traveller+6/13/09 WV USA
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Re: Gearbox Issues

Postby suzukix7 » Wed Mar 25, 2015 9:55 am

Looks like a strip down there is loads of swarf on the sump plug even with fresh oil and it still wont engage gear properly.
Clutch is now adjusted properly and the plates are all free and not gummed.
Do I have to buy the rotor puller though, is there something else to use.
I have a claw puller for the crankshaft sprocket.

Dave
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Re: Gearbox Issues

Postby suzukix7 » Wed Mar 25, 2015 1:43 pm

I've just been reading that you can use an m10 bolt to remove the rotor.
Does anyone know how to do this?
Do you just keep winding into the thread until the rotor pops off the shaft?

Dave
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Re: Gearbox Issues

Postby Agronski » Wed Mar 25, 2015 4:30 pm

Swarf in the oil could just be kickstarter-quadrant teeth - was with mine, the quadrant alignment is not exactly brilliant - see download/file.php?id=3446&mode=view

Check the clutch-side stuff first, because you can do that without cracking the case. You'll probably need an impact driver to get the clutch-cover screws out, though. And a new clutch-side gasket. I have a stencil if you're feeling brave and want to make your own from gasket paper.

As for taking the rotor off - yes, it's an M10 bolt, but file down the last few turns, otherwise you risk damaging the crankshaft inner threads where the points-cam bolt goes. The rotor is a taper-fit on the crankshaft with a Woodruff key, which (given the age of these things) will probably be stuck firmly in the crankshaft keyway.

Your TS is a later model, I think, so your primary sprocket will be the threaded-and-tapered duplex rather than the "two-screws" simplex as shown in the manual. You can use the claw puller, but a screw-on popper is better. You'll also have to take the clutch off, which means you'll need a spring-pusher (brace the bike against a wall, and put a sheet up behind you to catch the spring-cups). You'll also need a clutch basket stop. I made my own out of an old driven plate and some scrap steel rebar. See attached photograph - the diagrams in the manual are a bit hard to read because of the scan quality.
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Re: Gearbox Issues

Postby suzukix7 » Thu Mar 26, 2015 12:25 pm

Many thanks for that.
As regards the 10mm bolt to remove the rotor, do you just screw it through the centre until it lifts the rotor off the tapered shaft.
Like you said I am a little concerned about damaging whats behind it, obviously I can't use a claw type puller as this will damage the rotor itself.
So if I do file the last few threads off the 10mm bolt what will the bolt be pushing on? Just a little concerned as, as you say, I think it's gonna be stuck quitefirmly on the shaft after all this time?
All the clutch plates seem to be free and not stuck together at all and seem to move freely on the basket. I adjusted the clutch as you said and it was quite far out of adjustment but still got severe crunching and false nuetrals all over the place up and down the box. I have partially stripped it down to rotor and clutch still to be removed, taken head and barrels off so I suppose I may as well split the cases now as I can't find anything wrong with the clutch :(

Dave
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Re: Gearbox Issues

Postby Agronski » Thu Mar 26, 2015 3:02 pm

Behind the rotor is the crankshaft which has a tapped hole for the points-cam bolt - filing down the M10 means that you'll be pushing against the inner, rather than the outer part of this threaded hole. Doesn't really matter much, to be honest - as long as you don't have a bolt with a ragged end, you won't damage the very tough crankshaft metal.

Just keep winding the M10 in until the rotor pops loose - the rotor shouldn't be stuck hard to the shaft, but the Woodruff key might be. By the way, the inner of the rotor is also threaded, so once it's free, just pick it up by the M10 bolt. Hopefully you'll have remembered to take the stator/points assembly off beforehand, remembering to disconnect the electrical connections and being careful not to smash the regulator resistor with the socket wrench like I did :twisted:

Well, without looking at/measuring your clutch plates, you don't know if they're still good. The wear limit is only -0.2mm and they are probably the originals. But false neutrals etc. sounds like a worn selector and/or mis-aligned arresting bolt. Easy fixes, but yes - you'll need to crack the case. Rubber mallet and plenty of enthusiasm needed. Take photos - would be interested to see how the seals and the inside of the crankcase looks after 30 years...

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Re: Gearbox Issues

Postby suzukix7 » Sun Apr 12, 2015 7:31 am

Hi guys, I've just removed the crankshaft sprocket with an MZ puller.
The manuals say both Haynes and PDF download, that there should be a woodruff key holding the sprocket on to the crankshaft.
Mine hasn't got one or any recess where one should go, the shaft is just tapered and smooth?
My bike is a TS150 1979.
also I have just split the cases to investigate a gearbox problem but the right hand outer crankshaft bearing has stayed on the crankshaft instead of being left in the crankcase housing, is that right? If not, any idea how I will get it off the shaft at all. I will be replacing it as a matter of course.

Many Thanks Dave :?:
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Re: Gearbox Issues

Postby therealche » Sun Apr 12, 2015 8:57 am

It's OK not to have a woodruff key. Here is a picture from a parts list from some time post 76

Willkommen_bei_den_EastbikesUnited_-_2015-04-12_14.39.13.jpg


Which shows no key.

The crankshaft bearings do tend to stay on the crank. There is a clever tool for removing them.This is a cheap and easily bought one
http://www.screwfix.com/p/bearing-separator-puller/19315?kpid=19315&cm_mmc=Google-_-Product%20Listing%20Ads-_-Sales%20Tracking-_-sales%20tracking%20url&kpid=19315&cm_mmc=Google-_-Shopping%20-%20Car%20and%20Van-_-Shopping%20-%20Car%20and%20Van&gclid=CP-Ys8318MQCFYbItAodfB0AJw

, I tend to slide a cold chisel under the edge of the bearing and give it a light tap, then the other side and repeat until there is enough clearance to use a three legged puller to pull it off. Sounds brutal but it has always worked for me
ES250 Doppelport, ES250, ES250/1, ES250/2,ETS 250, ES150, ETS150, BK350, IWL Pitty, SR56 Wiesel, SR59 Berlin, Troll............ and thats just the German two strokes!
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Re: Gearbox Issues

Postby suzukix7 » Sun Apr 12, 2015 11:14 am

Many thanks for the quick reply, that's great.
Looks like a useful tool too, I think I will give it a try as you say the 3 legged pullers tend to have thick jaws that wont fit under the bearing.

Now all I have to do is figure out what's wrong with my gearbox lol!! nothing obvious at the moment and to be honest not getting a lot of help from any of the manuals I have.

Many thanks for the info, very useful mate.

Dave
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Re: Gearbox Issues

Postby suzukix7 » Wed Apr 15, 2015 12:42 pm

I have now checked the components on my gearbox and cannot find any signs of wear or damage.
The dogs are not damaged, the pinions are all in good condition as is the selector fork, as I said the bike has only covered a documented 5k.
However, I did check the gaps between the gears as stated and they were out. The dogs on 3rd gear were protruding out quite far. This is the gear that was jumping.
I adjusted the mechanism via the adjuster and locknut and third gear now sits a lot better on the shaft than it did.

Could this have been the reason for my problems ?

Dave
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Re: Gearbox Issues

Postby therealche » Wed Apr 15, 2015 1:50 pm

Definately a possibility, It always pays to pay attention to the adjustment of the gearbox.
ES250 Doppelport, ES250, ES250/1, ES250/2,ETS 250, ES150, ETS150, BK350, IWL Pitty, SR56 Wiesel, SR59 Berlin, Troll............ and thats just the German two strokes!
http://thecomeconcollection.blogspot.com/
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Re: Gearbox Issues

Postby suzukix7 » Thu Apr 23, 2015 2:53 pm

Guys, can someone advise me on adjustment of the TS150 gearbox.
The pdf file says that you take measurements when in 3rd gear and then in 4th gear.
The question I have is when in 3rd gear which cluster should be 13mm, the lay shaft cluster (short one) or the clutch shaft (long one)
The same question for the 0.2mm when in 4th gear, which cluster on which shaft should be measured?
It's probably me being thick but I can't make head nor tail of the diagram.

Any help would be appreciated.

Dave
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