My New Project

[DJRacing]

My new project is a YZ125B that I'm slowly putting together. The frame for this bike use to have a sidecar on it I think, as there were bits and pieces welded all over it on one side, even a grab rail at the back. So out came the grinder with a cutting wheel. Anyway all you 'old YZ125' fans might like to see the start of a project that will hopefully look like an OW11.

The YZ125 tank and straps. The tank straps a new.

The back of the seat base need to be cut shorter and the over-hang re-plastic welded back on.

Another pic of the tank and straps.

and again.

The project in its entirety..... a YZ125B as I see it.

[mx250]

A sidecar on a 125cc 

That a big project, a lot of work, up there with my Monty project. Good luck.

[paul]

gotta start some were good luck with it 

[DJRacing]

So far I have moved the mounting points on the tank and made the back underside of the tank wider and deeper and the mounting points for the tank on the frame lower and further back. Made brackets for the tank straps. Fitted new bearings and races for the steering and new bearing and bushes for the swingarm. The tank straps I made as will. The rear monoshock has been re-built and the travel shortened. The next step is to make the loop at the rear of the frame and brackets of the rear mudguard. I have to get a new seat foam and cut and mold it to fit the bike (with the correct look), then a new seat cover. I am in the process of building a motor (checking gearbox parts and trying to sort out clutches etc etc).

[yzhilly]

Nice work DJ i'm looking forward to it's progress . Hopefully it will inspire me to chase up a early yellow tank YZ250 deep in the heart of OZ .

[firko]

Cool project DJ. There's a lot of satisfaction to be found in building a bike up frrom a total dunger. To me, projects like this are what our movement is all about. Keep us updated on the progress matey.

[paul]

DUNGER  (beauty is in the eyes off the beholder) AS A MATTER OF FACT IVE GOT ME OWN DUNGER HAPPENING  TOO  SO NOW I DONT FEEL SO ALONE

[vandy010]

a real nice piece of work DJ.
one question though, i thought a 'B' model was still a twin shock same as the 'A' but in yellow. this looks to me like a 'C' with the 'A/B' style tank.
i don't care about correctness as i really like what i see. just curious.
juice me some more, 5 speed or 6?

[DJRacing]

Ok Vandy, my reckoning on the matter is that the 'B' model 125 should be like its bigger brothers the YZ250B and 360B which were monoshocked bikes with 'A' style tanks and tank straps, so I am building my own monoshocked 125 with the "A-B" tank and straps and a YZ250B looking seat. As for the front forks, they are the same as the YZ250B except the legs arent as nicely machined. I will be machinning the lower legs to give it a more werkys look. The motor for this project is turning out to be a little more difficult than I first thought. Originally I was going to use a set of '74 MX125A cases but have found that the gear box I was going to use was good but the selector drum is different at one end. I can fit a 6 speed box into the cases but cant select a gear so I'm going with 'C' cases and gearbox. I want to put an 'A' barrel and head on her, but first I have to check the reed block intake. I want to machine the intake out to fit a bigger reed block and port the barrel similar to a 'C' 125 or even an 'X'. It will depend on the transfer ports. The beauty of this project is that DT-MX and YZ stuff are all very similar around that period of time so it will be a bit of mix and match. I was looking at using mud-catcher rims, but I prefer the 'C' model rims so thats what will be going on for the wheels.

[vandy010]

sounds good DJ,
the 125 yamaha should'v built in 75.
pm on the way.

[DJRacing]

Yeah you got it Vandy- the real YZ125B

[firko]

DJ...I actually built a twin shocked version of what you are building back in the early 90's. I too tried to fit the 6 speed to the mx125a cases but had some sort of problem that I can't remember now. I ended up using the complete X model engine, I made a pipe out of a combination of the X and A items that looked like it was factory, even though they originally ran up oposite sides of the bike. I used 34mm MX250 forks and the X model wheels. Topped off with alloy bodied Konis, Webco head and a yellow plastic YZa tank (I think it was the larger 250/350 version) and straps.
Right from day one the bike was ilegal due to the post 1975 engine but with the Webco head the engine was disguised engough for it not to be noticed. I hadn't set out to build a cheater bike as I was actually building a legal 125 engine using a rare Noguchi top end and DG or FMF pipe (I think) to be fitted once it was finished. Unfortunately other projects got in the way and the Noguchi engine was never finished and the lot sold to a bloke on the condition that he didn't race the bike with the 6 speed engine. I only ever saw the bike once more before he sold it on to someone in the bush for short circuit racing.
I often wonder what ever happened to the Noguchi engine. Looking back I had a great time building the bike but soon realised that I was too big for the 125 tiddlers. My only regret is that I wrecked a pristine X model 125 and an equally nice MX125a to create the bike. X models were worth diddley shit back then and MX125a's were and still are not taken very seriously. Your project is taking the concept to another level. You're not destroying two perfectly good bikes to achieve the result, in fact you are doing the opposite by rejuvenating a pile of shit from a fate worse than death that will hopefully result in a cool little bike.

[DJRacing]

Firko, That was my orginal plan, to build a twinshocker, but I cant seem to bring myself to build a twinshock YZ  (dont get me wrong I love the "A" models but its the mono's that are my Elle McFergusson). So the plan evolved into using a YZ125C frame, which I didnt have. But I knew where one was that had so much crap welded on to it that I could actually bring myself to put a cutting wheel to it.
I have a real problem with cutting and hacking at orginal parts (because someone may need them one day, p.s. you HL boys lookout ) so thats why I'm going to go with the "C" cases. I wanted to put "A" sidecovers on as will but with the exhaust exiting the other side it would mean cutting up the "C" pipe or cutting up the "A" sidecover and molding up where the exhaust pipe would exit. I felt neither is appropriate. The motor that I will make up is from spares that I have acquired over the years that are just sitting around doing nothing. So far the only 2 parts I have had to alter to the point of no return are the seat and tank. As for the frame, it could go back to a "C" but then again I already have a white and a yellow "C" so what better use for a frame that had a bottom end of an IT175 in it and half a scap-yard weld to it. No parts on this bike will be newer than '75 but I assume that over there (Oz) it wouldnt be legal to race in pre75, but over here because we dont normally run pre78, flow on bikes with under-slung axles and the like are allowed to race pre75.
Firko did you take any photos of the bike??
At the moment I race a YZ125X in pre75, but I personelly feel that it is a cheater bike(not that I win on it, TMB kicks my arse), and the friendly (standing at the bar drinking) ribbing that I get from the boys about the YZ125X is all good but hopefully this bike will help .
I have been working on it now for about 2 months and by christmas I hope Santa can drop it down my chimney,(I will leave him a bottle of 'old bushmills' if he does
I am looking at painting the tank in white with Noguchi stickers.
Ahhh, the old 'a fate worse, than a fate worse than death' in the immortal words of Blackadder, a painter with a cutting wheel on a grinder...

[LWC82PE]

now i saw this a few weeks ago no bidders

http://cgi.ebay.com/Shinobi-water-cooled-head-Webco-FMF-DG-AHRMA-YZ125_W0QQitemZ280162024831QQihZ018QQcategoryZ43810QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

seller is 211suzuki up in QLD. the name rings a bell and i think he may be or has been a member of this forum.

could this have been any use to you? or not the right period? or wont fit? not hard to find or make a raditator for it.

just thought id mention it.

[Doc]

211suzuki = 211kawasaki  Mr. D Tanner