Another Z650...

[Bevelhead]

Here's my second Z650, one that arrived unexpectedly. Back in March 2021, I was offered a Z650 for free, from a chap who was more into old Brit bikes (he owns three Vincents), so wanted to move the Z650 on to someone who could rebuild it. Well, they say never look a gift horse in the mouth, so it was soon sitting at my mates workshop, as he'd collected it in his van for me.

Decided that one good turn deserves another, so a plan was hatched to get the bike back on the road as cheaply as possible, then give it to another mate, who was without a bike at the time. For various complicated reasons, that plan didn't happen. Here we are in 10 months later and the poor Zed is still getting in the way at my mates workshop.

Time for a plan B.

Last week the rolling chassis came back to my packed workshop, not sure where its going to go, but I'll squeeze it in somehow. Meanwhile the engine, which had been removed by the previous owner to fix a broken exhaust stud, will stay at my mates place for the time being.

The bike also comes with a couple of boxes of spares, which I haven't looked through yet.

A quick look over the bike shows its had a nice paintjob, pity about the awful Triumph-like tank decals.. which sadly are under the top coat of the paint. Will probably mean I'll have to respray the bike. The cheap Ebay rear shocks will have to go, as will the rusty exhaust. We think the latter is from a Zephyr, but with the large box under the engine removed. The seat is way too thick, not sure if its the OE seat with more foam? It'll have to be reupholstered or replaced. The engine has done 41,000 miles and looks tired, but was told it ran ok before it was removed.

Good points are that its a F2 model, so has the better 750E front end along with electronic ignition, while the stanchions are in good condition, possibly replaced or re-chromed in the past.

Having considered giving the engine a 810 conversion along with alloy swingarm 17inch wheels etc.. I decided against that idea. As I already have the Z650/1170, along with the MK2 with a 1400 big block, taken from my old turbo Zed. Therefore tuning this Z650 and massively upgrading it didn't hold much appeal, but then again nor did restoring it back to OE spec. So I guess the solution is to do a 'Resto-Mod', with small subtle changes that improve the power and handling/brakes, while still keeping it looking like a Z650. That said I just bought a cylinder block from a Z750.. it'll go straight on or so I'm told...





Ten months on a damp floor hasnt done the engine finish much good..

[Bevelhead]

Despite the rain, managed to get the the bike down to the frame and swingarm this afternoon. The wiring was in more of a mess than I realised, suspect its going to need a new charging system, and may rewire it with an M-Unit..


The OE front discs looked very worn, and sure enough they were way under the minimum thickness, so will have to be replaced. Given that the disc will need spacers to fit the 4 pots I want to use, it made sense to look into buying a modern pair of floating discs, since the work required to mount them will be no greater than machining the disc spacers I need anyway. Found a apparently good pair from a R6, so bought them off Ebay and they'll be here in a few days. They were suspiciously cheap, but perhaps I just got a bargain.. we'll see. By chance I already have a mint master cylinder from an R6 sitting in a box in the garage.

[Bevelhead]

The swingarm has a deep gouge in it, surprised it didn't go all the way through the wall of the arm..

[Bevelhead]

Swing arm now welded and linished to repair those deep gouges, next step is to give it an under brace..

[Bevelhead]

The replica Giuliari seat arrived, looks pretty good, not bad for £175.. its just resting on the frame in the pic, as hasn't been correctly mounted yet.

[Bevelhead]

Meanwhile, bought a rear light from an early ZX6R to replace the cheap after market one fitted when I got the bike, got to make a new mount for it next..

[zed1015]

Used one of those on my alloy cafe.
They suit the zed style tails really well.

tail light.jpg (185.16 KiB) Viewed 60183 times

[Bevelhead]

Great minds think alike

[Bevelhead]

The rear wheel had some small cuts and chips in its rim, on the chain side, so rather than buy another wheel from Ebay, had the damage welded and linished by my mate Geoff The Welder, at mates rates it was much cheaper than buying another wheel.

I was surprised at just how heavy the old mag wheels are, much heavier than the R6 5.5 inch rear wheel I just bought for the Mk2 project. I'll have to weigh them both soon before they get new tyres and discs.

Anyone know how heavy those old Mag wheels are?

[Bevelhead]

Making the adaptors to allow R6 discs to fit the mag wheels is proving to be tricky, as the seven mounting holes required cant be dialed in on the rotary table.. but clamping the two old discs together, they can be used as a guide to mark the seven centre points which need to be drilled. Meanwhile the PCD of the R6 discs and the Z650 Mag wheels are out by 1mm.. sigh. But we'll get there.

I was struck by the difference in weight between the R6 and Z650 rear wheels.. so I weighed them.. 5.4kg for the R6 Vs 7.2kg for the Z650. The forks are also surprisingly heavy, though haven't had chance to weigh them yet. I don't want to change the bike to modern 17 inch wheels, so unless a nice pair of Astralites turn up, the originally wheels will stay.

[Bevelhead]

With the disc adaptors done, we could see how the Yamaha gold spots look on the front end.. and they didn't look good. The problem is that the gold spots mounts are widely spaced, meaning a bracket would need to be very long. Which would look ugly. Time to dig out the pair of Brembo Goldlines I have and try those instead. Also note that with the discs moved further out, the speedo cable wont fit its drive anymore.. time for an electronic speedo.

[rpeters]

Making the adaptors to allow R6 discs to fit the mag wheels is proving to be tricky, as the seven mounting holes required cant be dialed in on the rotary table.. but clamping the two old discs together, they can be used as a guide to mark the seven centre points which need to be drilled. Meanwhile the PCD of the R6 discs and the Z650 Mag wheels are out by 1mm.. sigh. But we'll get there.

Sorry did I miss something here, I only count 5 mounting holes, but how have you mounted the discs? have you bolted the adaptor to the wheel and then bolted the disc to the adaptor?

[Bevelhead]

Making the adaptors to allow R6 discs to fit the mag wheels is proving to be tricky, as the seven mounting holes required cant be dialed in on the rotary table.. but clamping the two old discs together, they can be used as a guide to mark the seven centre points which need to be drilled. Meanwhile the PCD of the R6 discs and the Z650 Mag wheels are out by 1mm.. sigh. But we'll get there.

Sorry did I miss something here, I only count 5 mounting holes, but how have you mounted the discs? have you bolted the adaptor to the wheel and then bolted the disc to the adaptor?

YES

[Bevelhead]

The R6 discs and calipers have been fitted to the forks, and now just need to make a spacer to replace the speedo drive which wont be needed anymore. The fork mounts had to be milled down a few mm and the holes helicoiled to mount the bracket neatly, while the inner face of the slider needed a slight flat machining into it to clear the disc bolts. Its certainly not been an easy conversion. If I was starting again, I'd just fit the matching R6 forks too.. would have been a lot easier. I was planning on painting the fork lowers black and having the brackets hard anodised black too, but could also just polish both.. decisions, decisions..

[Bevelhead]

For the price of a packet of biscuits, a friend let me use his blasting cabinet to remove several layers of paint from the wheels. They will refinished in gold, not sure yet if I will paint them myself or get them powder coated.. the latter being more expensive but giving a more durable finish.

Meanwhile the frame has gone to be powder coated at Triple S, and has been taken back to bare metal. Which showed some rust damage to the frame, which they will get repaired before powder coating the frame.