And for my next trick ....

They have about 6" (5.9" actually I think) and when fully compressed, that puts the dust boot very close to the lower tree, maybe 1/2" away. And your fork brace will raise it higher and put it even closer.
 
Thanks, 5T. Looks like I'll have to rethink this a wee bit. More haste, less speed really .... I ought to know that at my age!

The problem is getting nothing, ie. the damper body or its piston, to foul anything with lock-to-lock movement. I think I fooled myself when I came up with a sweet spot and clearly hadn't properly thought it through. There will be an answer of course, but I may need to be a tad more creative. A bolt-on solution is proving a bit trickier than I first thought. Damn! I do enjoy a challenge, though.
 
I rushed out and bought an SR500 top yoke after reading an article that pointed out that the SR yoke has the same spacing for forks, brackets etc as the XS650 item but with the difference that it is flat. The XS yoke has the stem part some 35mm higher than the fork tops. The idea is that fitting the SR yoke will effectively lower the front of an XS by 35mm - steepen the steering angle, more weight over the front, handling benefits.

But then I thought about the issue 5T has pointed out, lack of clearance to the bottom yoke. So Miss November wears a cable tie around her right fork leg, which confirms that on a normal ride the fork lower gets a fair bit closer to the yoke than 35mm. I believe the left fork travels a similar distance.

So the SR top yoke is still sitting on a shelf in the garage. Maybe the answer would be to rebuild the forks to reduce the distance they compress? I dunno.
 
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Interesting.....although I must say that I have never felt a need for quicker steering on the XS650.

My '81 Special (the "Special-to-Cafe" donor bike), I did find very slow, but an XS650 Standard felt fine-fine to me.
 
Make & mount an L bracket off the two pinch bolts?
Would get the ball end pretty close to where it is now.


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Nice idea, Jim, I like it. As always, there's more than one way to do something but that's certainly an approach I'll mock up.

Problem #1 I think is exactly how much space there will be between the top of the fork brace and the lower yoke/tree on full compression. It might be sufficient for me to simply slide the existing clamp up. I feel some measuring coming on!
 
Well, here we are in mid-January and I've finished all this winter's work on the bike. In November I turned 65 and retired - got this present from my (older) brother, the bastard! I'll get him for this!

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But this from the kids. They know me so well:

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I got over the damper mount problem by making a little bracket from a piece of scrap steel I had. Here it is test-fitted, before cleanup and paint:

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The fork brace never came from Caferacerwebshop. I queried it of course and a very prompt and polite reply said Tarozzi were having manufacturing problems and what would I like to do? I wasn't in any hurry so decided to wait it out, curious as to how long it would take. After 3 months I gave up and emailed them to cancel the order which they did amazingly quickly - the money was back in my account within 20 minutes or so of sending the email. I think they could be better at liaising with customers when there are problems but I can't fault their responsiveness.

So I bought a Fastec brace from the UK.

View attachment 233713

I rebuilt the forks with new top bushes and Race Tech springs & emulators so that's it for the front end.

While things were apart I decided to replace the coil. At tickover, there is a steady beat from the left but some stumbling on the right, it's always been like that since I've had it, so thought I'd remove the coil and HT leads as possible sources of the problem. Naturally sod's law came into play and it's just the same now!

New coil had an interesting feature that made mounting it slightly awkward but some creativity with bolts & washers sorted things out:

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Next was the TX750 swingarm. I got this Polisport chain slider to protect things and drilled & tapped M6 holes to mount it - squeezing little grommets into the mounting holes with washers either side worked pretty well. I cut the bottom off of course, there's no need for that bit:

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It ends up looking like this:


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One thing to watch out for when mounting the TX750 swing arm is the clevis pin at the front end of the rear brake rod. It needs reversing to clear the swingarm, otherwise your nice new powder coating gets a gouge in it. Grrrrr .....

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Another gotcha is when drilling to fit a grease nipple, the nipple thread isn't long enough to bridge the bracing fillet and into the actual tube so I had to drill & tap it to M8 and Loctite in an M8 to M6 thread reducer. Here it is when I discovered the problem:

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There's also a new BT46 (successor to the BT45) on the rear and it all feels really nice and taut on the road. We've had a lot of rain lately and the roads are covered in 9 kinds of crap so I haven't done more than get a feel for things but that has been very positive, it feels great! And bloody well should do after all that effort! Here we are after today's 35-mile runaround and yes it now needs cleaning:

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Oh, and I discovered you get a 0.2V drop when turning on the headlight rather than a 2V one when switching from a 'normal' H4 to an LED bulb.
So what's next I hear you ask? Fit the new carb intake boots when they arrive from Sumo Rubber as that will eliminate leakage through cracked old rubber from the uneven tickover problem, and maybe have a stab at balancing the carbs which is something I've not felt the need to do so far as it all goes so well when off tickover. Apart from that, clean it and ride it!

Here's many happy miles for us all in 2023. Cheers -
Cliff
 
Great result from all your work! Lovely ride to look at and promises a lot from all the changes you've made.

I know what you mean about rain and 9 kinds of crap, the roads right now don't really encourage any spirited riding. But I'm very interested to hear your views on the steering damper, whether you can feel a difference and how? You might not have formed much idea after 35 careful miles . . .
 
Nicely done. Yes, as you discovered, the swingarm grease nipple must be located right at the edge of the gusset plate .....

Swingarm Grease Nipple 2.jpg


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And yes, the brake rod pin needs to be flipped around for clearance .....

RearBrakePivot.jpg


Another nice little mod is swapping in an older brake pedal pivot with a grease nipple. Yamaha eliminated the nipple around '81, probably a cost cutting thing. You can see all the extra wear on my original above probably because of that. The older one I swapped in is in much better shape.

RearBrakePivot2.jpg
 
Thanks, fellas. I did take the opportunity to clean & grease the rear brake pivot but one with a grease nipple would certainly be better.

@Raymond - I've had the steering damper on for a while, just with a different bracket. I found it to be a great improvement, makes the front feel really steady and not nervous at all. I wound the damping up bit by bit until it felt intrusive then backed off a click. Dunno if that's how it's supposed to be done but seems to work for me!
 
Well, the steering damper ally bracket failed even earlier than anticipated so time to sort something out that's rather more robust.
I've been monitoring fork travel and that confirmed there's easily enough room to use a fork-leg clamp so long as its tight to the bottom yoke, so what then to do about the frame-end mount? ..... My solution was to lock the rose joint on the damper body with a washer and add another rose joint, fixing that to frame clamp with thin washers here and there to ensure the roise joints' movement wasn't restricted. Seems to work, full lock-to-lock travel taking up the entire travel of the damper. The aim was a fully removable setup so both originality purists and folk like me who can't weld could take advantage; I think I've managed that with entirely off-the-shelf parts.
Proof of the pudding will be riding it of course, but it's been snowing here today so that will have to wait for a while! Here's the pics showing full lock, centre, full lock and detail pics at each full lock.

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I have to say that the Race Tech springs & emulators have improved the front end enormously but as I have this stuff I figured I might as well use it. It adds a bit of extra solidity to the feel. I'm looking forward to a trip to the Welsh twisties come the better weather!

Cheers -
Cliff
 
Sorry if this rambles a but but I'm sat here in Covid's tight embrace and feel, quite frankly, shitty. So bear with .......

The next phase of my 'continual improvement' plan has begun! I decided that I'd like a modest uplift in ooomph in the 3k - 6k range (or 3-5 if I have to narrow it a bit), and what I've been reading suggests that can be achieved by a change of cam and a careful smoothing in the ports with particular attention to port matching & blending with the inlets & exhausts to promote smooth flow of gases. And maybe, just maybe, at some point I could talk myself ito a 750 BBK .....

This is all going to progress slowly as the bike runs great as is so I'm in no hurry at all. But I could do with a bit more ......

This is the plan - I bought a complete head with matching numbers from Fleabay so I can create a nice top end separately, and one day pull the motor and swap the top ends. It looks like an '82 or '83 given the black paint, and naturally I have a few questions that I hope you can help with:

1. The cam is a 36T stamped 447 on one side, and 1 on the other. Does the '1' have any significance?
2. Is there any significance to the numbers stamped on the head & rocker box? Mine is 7S65.
3. There's more than one way to get to 750 - a Heiden Tuning/Mikes kit or the Smedspeed approach of removing liners, boring the block, then dropping in new liners are the ones I've seen so far but there may be others. Does one method offer a particular advantage over the other?
4. I plan on getting all the external paint removed (vapour blasting? There's a local place in Devizes) but would it be wisest to leave the internal surfaces painted? I understand it's there to aid oil return and maybe address a potential porosity problem. How likely is that really?

At some point I'll talk to Smedspeed about a cam regrind, their rocker arm refurb and frighten myself with likely cost of the 750 conversion but that's a way off yet.

Cheers all and I hope you're not similarly suffering.

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I don't think the "1" stamped on the cam means anything. The only significance of the numbers stamped on the head and top cover is you want them to match. That indicates the parts were machined together as a matched set for the bearing bores and probably the valve cover openings as well.
 
1. and 2. Far as I know, they're just casting numbers. They must have meant something to somebody at the factory at one time, but are pretty much meaningless to us now.

3. Iirc, having bore the block means the liners are made of thicker materiel... thicker walls. Means less chance of them going out of round due to heat/stress. Having liners too thick doesn't give the best heat transfer (loss), too thin runs the warping risk. Supposedly those you mentioned hit the sweet spot in the middle.

4. I'd leave the paint on the inside. If for no other reason than it'll cut the time (cost) of blasting just to do the outside. Not 100% sure Cliff, but I believe that's a powder coat. I know it's some pretty tenacious stuff from trying to remove it. Powder would explain why it's there. Masking takes time. In production time equally more money spent. Maybe that's the only reason it's there.... dunno.
And there's no porosity problems with the unpainted heads that I'm aware of anyway.
 
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Thanks fellas.

I just had another thought re paint removal - the guy I go to for powdercoating uses some chemical bath for paint removal - he can also put bigger things like bike frames in it and as his speciality is restoring mag wheels (he used to work for Dymag) he understands materials, so maybe I'll ask him what he thinks.

Cheers -
Cliff
 
I have not been sitting on my hands, and have decided to go the whole hog, as it were. A retirement present to me!! This means 750 BBK (Wiseco pistons option) from Smedspeed, plus their forged valves, Colisbro guides, recut seats, beehive valve springs, a moderate porting job by me, Shell #1 regrind (not arrived yet), new VM34 carbs.

I did opt for chemical strip followed by vapour blasting for the head + cam cover, and am very pleased with the finish.

So far I've assembled the 'adjusted' head and fitted the barrels & pistons, having already pulled through the new camchain.
Here's some pics of the Inlet work:

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And Exhaust:

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Not up to Jack's standard of course, but, I hope, not too bad for a first attempt, and good enough to make a difference.

Interestingly, I saw a couple of casting flaws on the Inlet side, but shouldn't be a problem as they don't go all the way through to the outside world. Dunno if this is common, but this is what I saw:

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I'm about stuck now, waiting for the new cam to arrive but also scratching my head as when the join in the camchain (I did split the old one at the rivet link) is at the top, the pistions are at BDC. The bike has had a top end job done by a PO, so I wonder if that person did something strange? It didn't cross my mind to check relative positions when I took the top end apart.
I think I'll have to join the camchain then fit the cam with the bearings off until I can get it in the right position with the pistons at TDC, then fit the bearings.

Unless someone has a better idea?
 
Nice work!

On the camchain, just wundering, if the tensioner was removed or loosened off, could the chain be lifted off to one side of the cam sprocket? Not sure how much free it has . . .
 
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