Roadster/Interstate/Thruxton R tank (2020)

Nice. And make sure your footpegs are always completely folded in. I managed to have mine a few minutes too far out once, and the sole of the boot caught it full swing. Got a small tear in my quad.

Thanks, I will keep that in mind when figuring out the design of the permanent footpegs. They are going to be folding type, but I'm hoping that the kicker will clear even if the pegs are out flat. That might not be possible from the sound of it..

Glen

Finally got back to working on this project today.
I plan to use a GSXR 600 brake at the rear. There are plenty of those on eBay US but not many on eBay Canada. Cross border shipping via UPS etc doubles the cost of the item, so that is out.
The land border has been shut to hobbyists for 18 months , but finally opened recently.
That allows for use of a freight receiver close by on the US side.
What an ordeal going across!
It was easy going down, the US Border Officer waved away all of my Covid Vaccination papers and said " have a nice day" I'm not sure this is a great policy!

Coming back into Canada was another matter. I needed all of the paperwork plus an online 10 page form that I had submitted before leaving. Even at that they didn't like the form and had me resubmit it at Canada Customs after waiting 1/2 an hour to get an officer to speak to.
In a way I'm glad to see all of the precautions Canada is taking, but it could be streamlined a bit.

Maybe the answer is to stay home and try harder to find stuff right here. Shipping from UK is also not difficult, will look harder there.
Fortunately I shouldn't need a lot from here on.


Anyway, I wanted to address the Carbs first. When first started, the bike would not run below 3k rpm, which was ok for a bit as the cam needed that anyway.
To sort that , last Spring I swapped the MK3 carbs over.
This 920 then ran fine. The MK3 carbs are back on the MK3.
Yesterday I gave the 920 carbs a good look over. These are near new 32 mm Amals that I purchased twenty years ago.
For the 920 I fitted them with new needle jets etc. I used a new pair of needles from my bag of needles. Somehow I got it in my head that these very short needles were the correct ones for Carbs that have the flat top spray tubes.
The ones I used are 2 v ring needles meant for 2 strokes. No wonder it wouldn't run properly!!
I now have what I think are the correct 3 v ring needles installed. The bike idles and runs perfectly, although I did not take it out on the road.
It also seems to start well.
After using the rollers for the first startup I restarted it with the kicker twice. This works ok as long as the bike is backed up to compression. Otherwise, forget it, it's not rolling over.

Glen

Fast Eddie said:

Yeah, like, Sick, bro.

As you can see, I’m very current.

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sure bruh

The last cross border UPS shipment cost $90 shipping +$83 in Border fees for $200 in parts shipped from Lynden WA to Langley BC, about 7 miles.

worntorn said:

Maybe the answer is to stay home and try harder to find stuff right here. Shipping from UK is also not difficult, will look harder there.


Glen

Click to expand...

I have to travel a lot for work Glen and have had to jump through unbelievably complex, constantly changing, and often downright illogical measures over the last year and a half, and my absolute conclusion is that’s exactly why they do it… simply to dissuade the masses from bothering to travel at all.

Nigel,
I was thinking that same thought while waiting at the Canadian border. The hoops Canada has in place do seem designed to greatly reduce traffic. It is certainly having that effect.
On the other hand the US agent was very welcoming and there was no Covid precaution at all. I spent about 30 seconds getting into the US and it's not my country.
It took nearly an hour of faffing about to get back into my own country!
That might be why the US has had more Covid infections and deaths than anyone else. The virus loves human freedom of movement.

So maybe the miserable Canadian Border agents and the difficult Canadian rules are helping for once.

Glen

Will definitely need to bulkhead this space.
This accumulation is from half a dozen trips up and down the gravel shop driveway after a rain. Also a couple of short rides on wet pavement.
The front mudguard worked well, very little crud got past it.

This bike needs a rear brake.
The rear wheel is a GSXR front wheel as the 3.5" wide GSXR front is pretty much the max for the Norton MK3 swing arm.
The GSXR front wheel uses a larger bolt pattern than the rear as the front brakes are much more powerful than the rear.
I thought about using a front disc on the rear wheel to get around this problem, but soon realized that creates more problems. First, the GSXR rear caliper I want to use is mounted on a nice lightweight alloy arm of the correct size for the axle and correct length for the small rear brake disc.
In order to use a large front disc on the rear, a new arm would have to be fabricated.
Secondly , and most importantly, an overly powerful rear brake is a very dangerous thing. That is why modern race bikes and sportbikes use the small rear disc and caliper. In this regard, the stock MK3 is modern. The front Norton disc is pretty weak, but the same brake on the rear is about perfect.
The third consideration is weight. This little rear disc is light.
So the answer was to modify the stock GSXR rear disc to fit the GSXR front bolt pattern and centre hole size.
The stock GSXR rear disc uses a 90 mm centre hole and a 110 mm 5 hole bolt circle.
The front uses a 100 mm centre hole and 120 mm bolt circle.
The Milling machine and rotary table were used for this.
Here is the rear wheel in need of a brake-

The Kearney & Trethewey mill



Bridgeport 16" rotary table

The disc was set up and centred to within .001" on the rotary table. The rotary table is not needed for the bolt hole work, but it will be for the centre work, so might as well mount it there.

The bolt circle program tells the mill operator where the new holes are going to be.
The operator sets the disc centre under the centre of the milling cutter, then inputs bolt circle info, number of holes, bolt circle radius. In this case radius is 60mm, number of bolts 5.

X&Y coordinates for the first hole



Y is on zero, X needs a tiny nudge. When getting within 2 mm bolt head and bolt hole icons appear. As the table is moved in the correct direction the bolt head icon slides over until it pops into the bolt hole icon at zero.

The modified disc fits. I made the centre hole at 100.5 mm to allow a tiny bit of clearance. It pushed on rather than dropped on, so that was ok.



I had OEM rear disc bolts. The shoulders were a bit long for this arrangement, yet another difference between front and rear. They weren't difficult to shorten on the lathe.
Here it is bolted up.

After I saw your first post on modifying the front rim, I was wondering how much meat there would be on the disc tabs. Not a lot of metal left under those bolt holes! Keeps the weight down, I guess. ;-)

There was still a good amount of meat as the holes moved inward into new territory. I didn't modify the rim in any way, just moved the disc holes out in the brake disc itself.
I suspect it would do the job with 3 of the 5 bolts removed, but I'll be using all 5!

I mistook you had changed the rim.

I was thinking about meat at the end of the tabs and looking at the modded ones it looks like the mount hole now is a U.

But I suspect you like.are correct.

That is correct and I did ponder the mod for quite awhile. I believe the failure point is still the 5 bolts that are in shear.
It will get tested with 2 bolts removed.


Glen

You've got mad skillz Glen. I envy your talent and capabilities.

Thanks. This job would have been difficult without the mill and DRO.
A machinist friend who is 80 remembers when their shop got its first basic DRO and then later a Mill DRO with the Bolt circle function.
Prior to that he would spend hours doing Trig calculations, checking calculations and then do layout. The DRO does all that with perfect accuracy in a few seconds.

Glen