Z1R Resurrection

[The Living Zed]

And an assembly of it all featuring the now legendary scanned chain cover.

[chrisNI]

Good work

[The Living Zed]

These are quite detailed parts and I’d used up most of my favours by now, plus I couldn’t ask anyone to risk getting dropped in the shit with the gaffers through making parts for me, so I sent the drawings to a few engineering companies to get quotes. One quote was massive, another was £710 but the best was £380 from TS CNC Ltd in Willenhall. I got two slabs of 6082 aluminium plate from Steel Express in Wolverhampton for £100. I already had the bearing. With the £36 for the piece of EN24 steel for the sprocket the mod had come to just over £500 so far. Needless to say TS got the job and they turned out really good.

[The Living Zed]

And it fits.

[The Living Zed]

I still had to extend the gear selector shaft and clutch push rod, but I could do that when I building the engine, so it was back to the frame and forks.

[r3sc]

Superb job! Nice work!

[Swirl]

Nice work there

[Al]

Its another level. Keep it coming its great reading.

AL

[sanderz]

Its another level. Keep it coming its great reading.

AL

Second that, this is at another level alright - im still in awe of the frame jig and the work gone into the frame thereafter.

[moizeau]

Absolutely fantastic skills. Those CMM's are great, we had a little one but most the time it was the larger one that we measured car body shells with that we used.
If I still lived in Burntwood I'd be asking for a guided tour of your workshop and toys.
Looking forward to the next instalment.

[The Living Zed]

So I’d already got an SRAD front end and needed to make yokes compatible to the Zed frame. The first thing I noticed about the USD forks is their lack of length, plus the SRAD front wheel is smaller. I’ve had scary tank slappers and a nasty Asda trolley and I know that if things ain’t quite right down there it’ll lead to heap load of trouble. I did some research into rake and trail to get an idea of typical figures just to be sure I wasn’t building something that was gonna spit me off at 120. By using the standard SRAD front end including the 32mm standard yolk offset it would’ve ended up with about a 23° rake and 67mm of trail, but I was looking for more like 26° and about 90mm of trail. The conclusion was to extend the forks. Perhaps not the most ideal thing to do, but it solved the problem. The other thing that became apparent to me when considering different yoke offsets was the steering angle at full lock. The closer the forks are to the yoke spindle (smaller offset), the smaller the full lock steering angle, but greater the trail. Inversely, the greater the offset (the further the forks out in front of the yoke spindle), the greater the steering angle, but the trail becomes less. I didn’t want a bike that needed a 38 point turn in a cul-de-sac, nor did I want a really twitchy front end. I felt a compromise coming on, but where and how was I going to find the happy medium? “I know, I’ll make some temporary yokes”, I thought “and see how they function”.

[The Living Zed]

Bit crude, but it served the purpose. After some trial and error I arrived at 56mm forks to yoke spindle offset (original Z1R offset is 60mm) and that gave me 38° full lock steering angle before the forks started caving the tank in. By making 126mm long fork extenders the rake worked out to 26.5° with an 85mm trail according to the CAD. When the bikes actually on the floor it'll probably be different, but I'll have to wait and see how it rides. Proof of the pudding 'n' all that.

[The Living Zed]

As you can see there, I’ve got some tidy slab yokes going on. I based the spindle on the SRAD one and got the bearing set from All Balls Racing to match the Z frame. A place called Rapid CNC in Brownhills turned the spindle and fork extenders for me and TS CNC machined the yokes and handle bar clamps.

[The Living Zed]

For the fork extensions I took the top cap out the fork leg, dismantled it and copied everything from the below the shoulder by the main o ring and just extended the portion from the shoulder upwards leaving the hexagon off at the top.

[The Living Zed]

Happy with the front end I moved onto the mono-shock. Tied up with string and supported by a block of MDF on a tin I was able to position the shocker to get some sizes for the lower rear engine mounts and the suspension linkage, plus I also found this really useful Hayabusa suspension layout drawing.