Resend my activation email : Register : Log in 
BCF: Bike Chat Forums


MZ rebuild- the hard part is done

Reply to topic
Bike Chat Forums Index -> Show & Tell
View previous topic : View next topic  
Author Message

lingeringstin...
Trackday Trickster



Joined: 01 May 2014
Karma :

PostPosted: 10:05 - 03 Sep 2017    Post subject: MZ rebuild- the hard part is done Reply with quote

Well I hope it won't be any worse than it was with the MZ engine on it. Pretty much the only shit left that's MZ is most of the frame, the headlight and the tail light now. Been far more work than it's worth but once I got stuck in I couldn't stop because I just couldn't allow the thing to get the better of me. Been fighting with this POS like that ever since the day I bought it and it will no doubt continue to annoy me until rust and general deterioration finally gets one of us.

https://s26.postimg.org/5te3qn7m1/stinkybob.jpg

Waiting for a few more bits to arrive in the post but I can't forsee any real difficulties in getting it going soon.
 Back to top
View user's profile Send private message You must be logged in to rate posts

stevo as b4
World Chat Champion



Joined: 17 Jul 2003
Karma :

PostPosted: 13:34 - 03 Sep 2017    Post subject: Reply with quote

The engine seems to sit in there quite nicely, with room to spare. Also very much looks like theres space for twin carbs too! Smile
 Back to top
View user's profile Send private message Send e-mail You must be logged in to rate posts

trevor saxe-coburg-gotha
World Chat Champion



Joined: 22 Nov 2012
Karma :

PostPosted: 13:52 - 03 Sep 2017    Post subject: Reply with quote

dem wheels
____________________
"Life is a sexually transmitted disease and the mortality rate is one hundred percent."

Mobylette Type 50 ---> Raleigh Grifter ---> Neval Minsk 125
 Back to top
View user's profile Send private message You must be logged in to rate posts

pepperami
World Chat Champion



Joined: 17 Jan 2010
Karma :

PostPosted: 13:55 - 03 Sep 2017    Post subject: Reply with quote

Mr Stnk, you are going into the top league of proper bikers when you get that back on the road Smile .
Ten out of ten!
I love the way it's made out many other bikes/parts.
____________________
I am the sum total of my own existence, what went before makes me who I am now!
 Back to top
View user's profile Send private message You must be logged in to rate posts

UnspeedySam
World Chat Champion



Joined: 25 Nov 2009
Karma :

PostPosted: 20:06 - 03 Sep 2017    Post subject: Reply with quote

Such an interesting project! Keep us up to date on it. Any idea what kind of horsepower the engine makes?
____________________
Riding: Honda Bros NT400 NC25 '88
Fixing: Honda VFR750 RC36 '94 and MZ ETZ 251 '90
Gone: ZZR600 '00, TRX850 '97, RXS100 '93, JS125-6B '07, BMW R1100RS '93, Kawasaki ZX-6R-J2 '01
 Back to top
View user's profile Send private message Visit poster's website You must be logged in to rate posts

lingeringstin...
Trackday Trickster



Joined: 01 May 2014
Karma :

PostPosted: 21:08 - 03 Sep 2017    Post subject: Reply with quote

stevo as b4 wrote:
The engine seems to sit in there quite nicely, with room to spare. Also very much looks like theres space for twin carbs too! Smile


Unfortunately the engine probably won't be in there exactly like that. The rear motor mounts are modified MZ mounts and actually hinge where they connect to the swingarm gubbins and although they keep the engine from moving laterally I had to make a front down tube to suspend it all from and it's not quite finished.

There's a temporary brace from the head to the frame that will be a tad shorter when I make a real one and the whole engine will be rotated slighty rearward by an inch or two which is JUST enough to cause problems fitting carbs. It's the funny shape of the MZ frame behind the tank.

I tried a few different carb attempts and the only thing that actually fits without any insane routing or other trouble is the stock manifold from the quadbike that takes a single PZ30. I've already bought a new carb, which was quite cheap, so I'm going to use that initially to get up and running. I might start mucking about with other carbs later after I know it goes.

I've ended up using the quadbike two into one exhaust which will be piped through a couple of VW tailpipe baffles connected end to end in more or less a straight line from front to back, sort of high level style.

I was going to use Honda Rebel twin exhaust and even sourced a decent set but when they arrived they weighed a fucking ton and the header pipes turned out to be too long for my low bike and I'd have to cut about three inches out of each one for ground clearance. Then I'd have to weld them back together and they're double walled pipes so it could get ugly since I'm no master welder and it just all looked like too much work that had the potential to end badly so I just decided to go with the sawed off quadbike pipes and flog the Honda exhaust later.

The wiring is all done apart from the coil wires. I'm using a tractor ignition switch (with a real key and everything!) because of the electric start. I had to remove the MZ battery box so that's where I stuck all the electrical shit and the battery will live in a box on the side now.



Where the battery goes now:

https://s26.postimg.org/s6aekmtl5/CAM_1087.jpg


https://s26.postimg.org/5vmjknwax/CAM_1093.jpg


Last edited by lingeringstink on 21:59 - 03 Sep 2017; edited 1 time in total
 Back to top
View user's profile Send private message You must be logged in to rate posts

lingeringstin...
Trackday Trickster



Joined: 01 May 2014
Karma :

PostPosted: 21:18 - 03 Sep 2017    Post subject: Reply with quote

UnspeedySam wrote:
Such an interesting project! Keep us up to date on it. Any idea what kind of horsepower the engine makes?


In standard trim they claim to make only about 18hp but I've seen scope for tuning when I was rebuilding it so I might start mucking about making another engine with strange modifications after I get it going first. 18hp isn't much but the bike weighs nothing, certainly very much less than a Honda Rebel, and the MZ engine was only about 20hp and it got me by for a long time. I'm used to it.
 Back to top
View user's profile Send private message You must be logged in to rate posts

pepperami
World Chat Champion



Joined: 17 Jan 2010
Karma :

PostPosted: 22:30 - 03 Sep 2017    Post subject: Reply with quote

Err am I missing something or are those rear shocks really skinny? Smile
____________________
I am the sum total of my own existence, what went before makes me who I am now!
 Back to top
View user's profile Send private message You must be logged in to rate posts

lingeringstin...
Trackday Trickster



Joined: 01 May 2014
Karma :

PostPosted: 22:54 - 03 Sep 2017    Post subject: Reply with quote

pepperami wrote:
Err am I missing something or are those rear shocks really skinny? Smile


Rear shocks? What's rear shocks? Is it some sort of newfangled motorbicycle accoutrement they put on modern rubbish? I'll have to go down to the library and peruse The 1933 Book Of Knowledge to see what that's all about.
 Back to top
View user's profile Send private message You must be logged in to rate posts

stinkwheel
Bovine Proctologist



Joined: 12 Jul 2004
Karma :

PostPosted: 10:10 - 04 Sep 2017    Post subject: Reply with quote

pepperami wrote:
Err am I missing something or are those rear shocks really skinny? Smile


They look like a significant upgrade from the last time I saw the bike. Pretty sure it used to have rusty box section in there.
____________________
“Rule one: Always stick around for one more drink. That's when things happen. That's when you find out everything you want to know.
I did the 2010 Round Britain Rally on my 350 Bullet. 89 landmarks, 3 months, 9,500 miles.
 Back to top
View user's profile Send private message You must be logged in to rate posts

lingeringstin...
Trackday Trickster



Joined: 01 May 2014
Karma :

PostPosted: 12:54 - 04 Sep 2017    Post subject: Reply with quote

stinkwheel wrote:
pepperami wrote:
Err am I missing something or are those rear shocks really skinny? Smile


They look like a significant upgrade from the last time I saw the bike. Pretty sure it used to have rusty box section in there.



Oh yes, I've gone all fancy pants on it now. Those are brand new turnbuckles so I can have some slight adjustment for height. Bottom end is a rod eye and the top end is the top of some MZ shocks stuck on with some threaded bar, all with lock nuts and washers even. Very posh.
 Back to top
View user's profile Send private message You must be logged in to rate posts

pepperami
World Chat Champion



Joined: 17 Jan 2010
Karma :

PostPosted: 15:09 - 04 Sep 2017    Post subject: Reply with quote

Why no shock absorbers?
Just interested.
____________________
I am the sum total of my own existence, what went before makes me who I am now!
 Back to top
View user's profile Send private message You must be logged in to rate posts

lingeringstin...
Trackday Trickster



Joined: 01 May 2014
Karma :

PostPosted: 20:45 - 04 Sep 2017    Post subject: Reply with quote

Well you asked. It all started about 20-odd years ago when the bike was due for an MOT and the shocks were leaking. Somebody told me if you didn't have shocks they couldn't fail it so I cut up some dead straight handlebars and welded the old shock mounts to the ends of a length of straight handlebar section. I was just skint at the time and didn't want to have to pay out for shocks and this seemed like a cheeky way to get through the MOT.

Then once I started going around on the bike like that I grew to really like it and I just never went back to rear shocks. Over the years I learned what the perfect air pressure was for the tyres I was using to give me just enough squish over bumps but not feel all sloggy and slithery on the road. The problem with that was that once a year I had to pump my rear tyre up to 32PSI for the MOT and then let it back down again afterwards for road use.

I discovered that when riding on iced over roads it was actually a lot better because it was lower but it was also stiffer and therefore more manageable and I found my bike could go places normal bikes would struggle to go when the roads were packed ice. It was my winter courier hack of choice. It was low to the ground and much more useful on ice and snow.

Over the years people always said I was crazy and that it must hurt my back but it was actually a million times more comfortable than having MZ shocks. My seating position had me actually bent leaning forward slightly (straight handlebars, low seat) which meant my body just flexed over road bumps as opposed to being kicked right up the spine the way apehanger hardtails do you.

I actually found that distance journeys were far more comfortable than they were when I had shocks. I could go all day without ever stopping and I didn't feel knackered or have a sore back. It was great. Of course nobody believed me but I didn't care. I just never ever went back to shocks again. It also made my chains last longer and my tyres wear more evenly. And being low to the ground was a lot more stable in sketchy conditions. The only time I didn't like it was when I went green laning and parts of our route took in things like rough ploughed fields, stream crossings, deep muddy uphill ruts and paths strewn with chunky boulders but I could forgive that as it's not really what my bike was designed for. It did do me proud though.

I'm just used to it now. Every time I'm on a bike with shocks now it seems strange and I don't really feel like I'm in control as much. It does require getting to know what's the right tyre pressure to run for any given rear tyre but once you get it right it works great. The lower air pressure even means better grip on dodgy surfaces and will naturally low gear you if carrying a heavy load by the tyre squishing down more.

I think there's a lot to be said for properly set up hardtail bikes. Hardtail is great for all kinds of reasons, on and off the track, that people don't even think about anymore since virtually everything nowadays is automatically designed with suspension. I absolutely love this hardtail setup with the dead straight handlebars and forwardly bent posture. I've never had a more comfortable bike for long distances or all day courier work. But hardtail sat bolt upright over the rear wheel with ape hangers is just terrible in every way.
 Back to top
View user's profile Send private message You must be logged in to rate posts

UnspeedySam
World Chat Champion



Joined: 25 Nov 2009
Karma :

PostPosted: 20:25 - 05 Sep 2017    Post subject: Reply with quote

All hail Teffers mk2, ratbike edition!

edit: Actually read the post now. Laughing I think I'm hardtail curious now...also I kind of want to know how your contraption rides when it's back on the road.
____________________
Riding: Honda Bros NT400 NC25 '88
Fixing: Honda VFR750 RC36 '94 and MZ ETZ 251 '90
Gone: ZZR600 '00, TRX850 '97, RXS100 '93, JS125-6B '07, BMW R1100RS '93, Kawasaki ZX-6R-J2 '01
 Back to top
View user's profile Send private message Visit poster's website You must be logged in to rate posts

lingeringstin...
Trackday Trickster



Joined: 01 May 2014
Karma :

PostPosted: 23:04 - 05 Sep 2017    Post subject: Reply with quote

Hardtail used to be the way it was done. Back in the day there were even hardtail trials bikes but once hardtails became fashion statements and copies of Easy Rider choppers it all went to hell. If you sit bolt upright with your legs akimbo and your arms reaching up for the apehangers then every road bump will pound your spine to death.

On my bike you actually lean forward to the straight handlebars with a slightly bent back and you flex with the road bumps instead of fight against them. I doubt you'll ever come across a hardtail without an idiotic seating posture nowadays. Mine is an improvement on the way it was, but that's usually not the case. Maybe some drag bikes are hardtail but most every other hardtail you'll ever see is pretty much just a fashion statement that rides worse than if it had shocks. They might be fun to look at but they're probably not great to ride.
 Back to top
View user's profile Send private message You must be logged in to rate posts
Display posts from previous:   



MZ

£152 - 7 Bids

MZ

£3989 - Classified Ad

Other Motorcycle Parts

£17 - Buy It Now

Batteries

£33.58 - Buy It Now

Other Motorcycle Parts

£3.20 - Buy It Now

Other Clothing & Protection

£44.99 - Buy It Now
Post new topic   Reply to topic    Bike Chat Forums Index -> Show & Tell All times are GMT
Page 1 of 1

 
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
You cannot attach files in this forum
You cannot download files in this forum

Read the Terms of Use! - Powered by phpBB © phpBB Group
 

Debug Mode: ON - Server: discovery (www) - Page Generation Time: 1.34 Sec - Server Load: 0.7 - MySQL Queries: 17 - CDN Objects: 35 - Page Size: 94.79 Kb