Help me with my Sachs...its simple

Matt Wilson /

I just bought a running Sachs moped today in pretty good condition. The bike already ran about 25mph but it had a few quirks. I went through and did the usual "fred's guide tune up"

I also removed most of the rust with muriatic acid.

It has a 52 main jet and a very restrictive looking airbox...so I think that I should be able to get another 3-4mph with some tuning. It also has the cutest bing carb ever...its so tiny...and its rectangular, not like the ones on puchs

So the bike shoudl run great...BUT I've got a big problem that probably has a simple solution.

I wanted to check the transmission oil, so I pulled the fill to plug. Nothing came out. So I unscrewed the top plug and added the trans oil until it ran out the bottom plug.

Now I can't get the top plug back in! What am I doing wrong?!

It is a long bolt as you can see in the pictures below, and has threads on the top. It is not stripped, but it won't go into the transmission case far enough to allow the threads to catch. I have tried tapping it in with a hammer, I've tried hammering and screwing at the same time. I've also tried pedaling and screwing at the same time.

I am threading the correct way.

I thought that perhaps there was a burr on the lip so I sanded it with my dremel. It made no difference. I also tried making the bevel at the end shaper so that it would slide in easier..still no luck.

Take a look at the pictures and see if you can help.

<IMG src=" http://www.rpi.edu/~wilsom/a.jpg"> ;

<IMG src=" http://www.rpi.edu/~wilsom/b.jpg"> ;

<IMG src=" http://www.rpi.edu/~wilsom/c.jpg"> ;

Thanks

Matt

Re: Help me with my Sachs...its simple

Dave Gregory /

lol i bet right now u had a puch????then u wouldnt have this problem

~dave~

Re: Help me with my Sachs...its simple

Matt Wilson /

I have a puch maxi, a peugeot, a sachs, and a newer yamaha scooter.

And actually the sachs are very similar to the puchs....but one thing that makes them better is a removable gas tank.

Do I need to get the transmission in a certain position to remove this bolt?

And sorry for the amount of time it takes for this page to load.... I know I'm on a shitty internet connection too

Matt

Re: Help me with my Sachs...its simple

....unrelated.....but if those tires are 17's who makes em........im looking for a white wall..........thanx

Re: Help me with my Sachs...its simple

If you do get 3-4 miles faster out of an air filter or carb work without putting in a bigger jet do me a big favor and tell me how....i would like mine to do at least 30

Re: Help me with my Sachs...its simple

Matt Wilson /

Andrew the general idea is to keep the ratio of air to fuel the same but increase the amount of mix that goes to the engine.

To do this you want to modify the airbox so that more air is getting to the carburator, and also increase the size of the main jet. This will allow more air/fuel mixture to reach the engine.

Fred doesn't reccomend doing this, because he says it can mess up the air flow charicaristics of the bike. I have noticed positve results 3mph on my puch and peugeot so I would. Others have found that theory works on tomos as well. But don't blame me if it messes the bike up.

Do not remove the airfilter or modify it, just change how the air gets to the filter

Matt

turn it the other way

those threads look reversed in the pic, try turning the screw the opposite way. they look like their lefty tighty righty loosey (the opposite of normal threads).

-Garret

I did the same thing!

Alright,

After having a tomos for 2 years I figured, just as you did, that the transmission fluid goes into that top screw. Boy, were we wrong.

The only way to get transmission fluid into the sachs 505 case is to tip the moped to the side and while using a funnel, pouring the fluid into the side hole until, when you right the bike, it comes out.

So, what to do with this incredibly long bolt? Well, you're going to have to take the side of the case off. Unscrew the five screws out and look out for the flood of fluid that will come out when you pop that plate. There will be a spacer about an inch long and an arm (that at the end connects to the compression cable) which swivels on that long bolt. On the bottom of the case will be a hole for the end of the long bolt to go into. Slide the long bolt into the top of the case and replace the arm and the spacer onto the long bolt. Make sure that the spacer is on the bottom. (I unfortunately didn't do this right and let it go for quite awhile, d'oh). Screw in the long bolt all the way, slap on the plate to the case and fill up your case with type-f.

There you go, you're ready to enjoy the quick acceleration of a sachs engine. Hope this helped.

--Jake

Re: I did the same thing!

wow!

Yeah, I was gonna say, I am fortunate enough to have a manual for my Sachs, and it says to use the hole on the side for the tranny fluid.

So getting that thing in must be a chore.

The transmission exploded

Matt Wilson /

After trying to tap the bolt into the hole for another hour, I removed the transmission case. When I looked inside I saw this...every thing was exploded. Jake you were absolutely correct.

<IMG src=" http://www.rpi.edu/~wilsom/w.jpg"> ;

and this

<IMG src=" http://www.rpi.edu/~wilsom/x.jpg"> ;

What does this brass adjustment screw do?

<IMG src=" http://www.rpi.edu/~wilsom/y.jpg"> ;

and

<IMG src=" http://www.rpi.edu/~wilsom/z.jpg"> ;

I put the transmission back together and I must have messed something up. The bike is hard to pedal. I tried draining the trans fluid to see if it made a difference. Nope.

Jake could you please please please scan me the pages from your manual that cover the transmission. I would really really appreciate it.

Also when you pedal your bike is there resistance, or does the ped ride like a normal single speed bike

Matt

Re: The transmission exploded

Matt Wilson /

Oh sorry brian can you please scan a couple pages from the manual for me....please

Matt

Re: The transmission exploded

I don't have a manual thus when I put mine back together, I screwed it up. Later, I realized my mistake and no harm was done.

While taking a look at your pictures, I realized that mine doesn't have that spring in the arm. I have no idea why it doesn't but it works fine. When I peddle, it feels of normal resistance.

The end (not near the brass piece) of that arm has to connect to the end of the decompression cable. Then slide in the long bolt with it going in this order:

top

arm w/spring

spacer

bottom

Now, I have some questions for you:

does it engage the decompression when everything is put back together?

How much harder is it to peddle?

could you take a picture of the bolt assembled with arm and spacer?

hope I could help

--Jake

Re: The transmission exploded

I lost my manual, I'm sorry. : (

STEP AWAY FROM THE MOPED

OH JESUS- PUT IT DOWN AND BACK AWAY!

OK calm down....

There is such a thing as a flexible funnel, available at most auto parts stores. You put the end in the little hole and fill it there, on level ground. They sell them to fill up transmissions.

Your long screw is the pivot for the starting clutch. Make sure that your cable is still attached, thread it up and thru your decompression valve and to the handlebars.

the order for re-assembly is: spacer, lever and then spring. The spring has a short tang on the end that rests against the lever, and a long one that you push inside the case when you have it assembled. The spring pushes the lever out, away from the clutch by twisting.

Before you put the aluminum cover back on, check that your clutch is adjusted right. You can tighten it by adjusting that little brass screw.

Man that's a lot of trouble to get into in one night.

Re: Help me with my Sachs...its simple

Ha!..... I did the same thing------ WRONG MOVE---- that bolt holds the clutch arm and spring, now pull that cover and put it back togeather.... I never figured out where to add fluid.... I junked mine! Did save the engine for parts. Doug D.

Re: STEP AWAY FROM THE MOPED

Matt Wilson /

>>Man that's a lot of trouble to get into in one night...

Yeah, and unfortunatly the transmission was one of the few things that was working well when I got the bike. If I only knew that the top bolt was not a fill hole, I would not have any of these problems. I don't have any problems filling up the transmission, mbartell, but thanks for the funnel and tube tip. I may get one anyways

I reassembled the trans last night, and it seems that everything is in place, but it feels like the bike is hard to pedal. I rewired the decompression cable, and put it through some new housing.

I set up the spring so that the hooked end spring pushes against the outer transmission plate (The one that is held on by 5 screws.) Is this right or, should it push against the clutch, ei. face the other way.

I'm pretty excited to get this bike to work. This is the only thing that I have left to do.

And when I removed the plug it was black and sooty, so I think removing the back of the airbox will help a lot.

Also what does adjusting the brass clutch screw do? Quicker take offs?

This is the 25mph version, so I'm guessing that it is a one speed. Right?

Matt

Re: STEP AWAY FROM THE MOPED

Matt Wilson /

Now, I have some questions for you:

does it engage the decompression when everything is put back together?

Yes, I was able to rewire the decompression, and when I pull the lever and peddle it makes the usual pfft...pfftt.

How much harder is it to peddle?

Well I only rode the bike for 5 minutes before, but I am definitely pushing the transmission, the power is not direct pedal to rear wheel... I'm losing some somewhere

could you take a picture of the bolt assembled with arm and spacer?

Yeah I'll do that later today. Thanks for helping me out guys

Matt

Re: STEP AWAY FROM THE MOPED

The spring goes under the clutch arm, and you have to take a screwdriver and pry the end of it into the engine case. that means wrapping it further around the shaft, towards the front of the bike. If you don't it won't idle. The brass screw helps with the starting, so you don't have to pull the lever so hard when kicking it over.

Looking at sachs clutches, the way I figured to make it grab harder would be to change out one of the thin metal plates for a thicker one, if it will fit. The other option is to get a heavier weight behind the clutch. It looks like a ring or bracelet behind the clutch, as the motor spins, it stretches out and puts pressure on the clutch. I'm not sure if anyone makes a heaver weight for them. Part of the mystery of a fast sachs.

I can't tell from your pictures, but it looks like you do at least have the larger exhaust pipe. the square cylinder head would also help get you easily past 30 mph. It has bigger intake and exhaust ports.

Good chance that your exhaust pipe is crudded up, so clean that out too. The champion plug has worked best for me lately, so you may want to look for one. the NKG's were second.

Re: STEP AWAY FROM THE MOPED

The decompression should engage when you pull the cable. It only needs to move a little bit, and it springs shut automatically when you let go. Sorry, but I may not be able to get a picture of the clutch set up immeadiatly.

I'm not too familiar with the set up inside of the 505 motor. there is a gear that moves and engages and disengages the pedals. It also handles your brakes freewheel- style.

I have the 504 motor, without the attached pedals. I have a 505 case lying around, that I could tear into to look, but that may take a day or two.

Now I think I know why there arn't that many Sachs people around- there's not a lot to them, and are pretty easy to mess up , if you'r not careful.

If I have the time I should put together a specific guide. I guess I need to get a manual first... Pictures would realllly help.

Re: STEP AWAY FROM THE MOPED

Matt Wilson /

>>The spring goes under the clutch arm

What is the clutch arm? Is it part that I am holding in teh last picture?

Can you please describe it more.

I installed the spring as it is in the last picture. The straight end of the spring went behind the arm, and the looped end went in front of the arm (pushing against the outer transmission plate)

I installed everything in the right order, but I think that perhaps my spring position may be incorrect.

Is this right? I had a little trouble following your previous post

Thanks

Matt

Re: STEP AWAY FROM THE MOPED

Matt Wilson /

Mbartell, let me know if you want me to take any pictures of my bike. Feel free to use them if you like

Also when you say that the champion spark plug works beeter than and NGK what differences did you notice...top speed, ease of starting, accelleration, ect

Matt

Re: STEP AWAY FROM THE MOPED

The spring goes under the arm- the piece you are holding in the picture. It should be oriented the same way, just under the arm. The bolt goes thru the spacer, lever and center of the spring. The end of the spring that has the hook will kind of stick out, after you have all the parts in the right order, and bolted into the case. Pull the hook around the pivot bolt and push it on the other side of the little ledge in the engine case. That way the spring will have tension in it, and won't be pressing against the cover.

Re: STEP AWAY FROM THE MOPED

The champion plug gave a bigger spark outside of the motor, much easier starts. It felt like it gave me a better take off.

I don't know about the top speed because I have been running around with no spedometer for a while. With my set-up it even worked better than the Bosch platinum plug that everyone swears by here.

Did it work???

Did you dis and re- assemble your moped yet?

just curious, and I like to try and follow up on stuff.

goodness.. still having trouble with this

So,

after some contemplating and thinking about this whole situation I thought about how I didn't have that spring at all in my transmission. I thought it was weird but really it was a passing thought. But more and more it was eating me up about how it was missing and if it was really just hiding from me in the transmission case.

Today I took off the case plate and looked around. Lo and behold it was hiding in there. All this time I had been riding around with a metal part in close proximity to the clutch. I'm very lucky I didn't royally screw my moped up. But there is some confusion on where that damn spring goes. Under, in between, or on top of that arm. I'm still not 100% sure but the attached photo will help us out. It shows the spring being under the arm. So, Matt, I've been telling you lies this whole time. Take a look for yourself and let me know what you think. You too MBartell.

--Jake

sachstransmissionpict.jpg

Re: goodness.. still having trouble with this

Matt Wilson /

Thanks so much jake

I haven't had the chance to try out the ped because the petcock leaks..but I should have a new one in a few days

That diagram actually looks like it might not be right???

I thought that the proper order was

7

6

3

4 with the spring going between part 3

5

This seems really wierd..the way that they have it in the diagram doesn't even seem like it would work???/

Even more confused than before

Matt

Re: goodness.. still having trouble with this

The diagram is right. It just dosn't show the case. the spacer is on top of the arm, and the spring is under it. The spring holds the arm up, and that's why you need the spacer on the top. The washer on the very top is against the screw-head on the top of the case.

Follow the diagram and it will be fine. I'll dig up a camera, take a picture and probably have it monday,

I didn't want to change my tranny fluid, but just for clarity's sake I'll do it.

Re: goodness.. still having trouble with this

Matt Wilson /

Jake,

Did you have any problems without having a clutch spring?

I'm surprised that the bike had any pick up at all.

And this is actually exactly how mbartell descibed it in an earlier post.

I think I'm going to put it back together as shown in the diagram.

Thanks again... and after reading mbartells earlier post this makes sense.

Sometimes a diagram makes a huge difference... I don't think that I could have ever figured that out just from a discription

Where did you get the manual? Is it online somewhere?

If you scanned it would you mind scanning a few other pages? I don't really need them but it would be nice to avoid something else like this....

Thanks

Matt

Re: goodness.. still having trouble with this

I got this picture from the moped junkyard site. I also have to go and take everything apart right after I just put it back together and filled it up with trans fluid!

Yeah, surprizingly enough the moped worked without that spring. The only difference was that it was shifting real squirrely, like a tomos normally does.

btw, there is a sachs engine manual on auction right now on ebay. just search from sachs motor.

--Jake

whoops

I'm sorry, the engine manual auction must have ended. I was up a couple of days ago, though.

--Jake

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