XR11/73

[Suzukidave]

Very sturdy looking cylinder puller tool nice idea with the head bolts and i really like the vintage racing tail / seat

[garry55]

thanks for the positive comments Dave
think I have resolved the upper rear engine mount problem - just a bit more engineering to do.
more good news is that I have had a couple of mates measuring front suspension travel on their bikes and it maxes at 2.5" which gives me adequate clearance for the centre header pipe now its been shortened.
hoping to crack on with it now as it has to be finished for early August.............

[Suzukidave]

When we were setting up for the chamber design on the SRAD bike i lowered the forks through the triple clamps the amount of the fork travel so i could easy see just how tight the bend out the exhaust port had to be .

[garry55]

can you remember how much you dropped the forks Dave?
I'm thinking 3" should be adequate.

[Suzukidave]

You had posted that the front had around 2-1/2" travel ( sorry i cannot quickly think what that would be in mm ) so i too would think 3" should give ya a margin of clearance for safety

[garry55]

just checking if my findings were in line with what you had already sorted for your bike
I've fitted the lowest profile front tyre I can find and, allowing for tyre growth when hot, 3 inches should be sufficient. Just have to make sure I brake with the front wheel straight ahead !

[garry55]

at a loose end today, so stripped one of the GK73A fuel tanks and gave it a good rubbing down...........





its in a remarkable condition for a 25-year old tank - just 1 tiny dent to attend to and no rust. Gave it a couple of coats of rattle can primer...........







and left it hanging in the conservatory to dry overnight - if the weather is kind tomorrow, I'll try and get some colour on it

[garry55]

spent a couple of hours tonight sorting out the seat fitment - its a TR750 replica.







more painting...............

[garry55]

more progress - after much deliberating about how best to solve the rear upper engine mount, its now sorted.

opened up the original mounting bolt holes from 10mm to 20mm, measured the gaps left and right, then turned up these 2 top hat spacers, 20mm outer diameter, bored 10mm to take the mounting bolt.



then I had to mark where the top hat sat on the frame weld



and grind it flat



with this done on both sides, the top hat spacers could sit flat on the frame plate and aligned





and with the motor in place



once tightened, this mount will hold the motor in place with no other support, so it must be OK

easy job next, making the lower rear mounts, before it goes to have the front mounts welded on.

[garry55]

the lower rear motor mount - the easy one. Acouple of hours at home roughing-out the bracket shapes



then to work last night for final shaping





now awaiting the attention of my welder - hopefully I will be able to collect it when I return to work on Tuesday, fit it on Wednesday and then leave the rolling chassis and motor with my other welders to have the upper mounts attached whilst I am away at the Isle of Man TT.

[garry55]

not a lot of progress on this project, due in part to me pushing to get the V4-500 project up-and-running and an impending house move that is playing havoc with my domestic life.
I have, however, been thinking about the front tyre / centre header pipe interference problem that manifested itself when I fitted the front 17" Aprilia wheel and tyre and have come up with the following plan to create a much needed extra half-inch of clearance :-
First-off, I have purchased a 16" FireBlade front wheel. The original tyre fitment for these bikes was a 130/70 - 16. There isn't a big choice of tyres out there in this size, but I have discovered that the Avon AM22 front race tyres come in a handy 120/70 -16 size which, in an ideal world, saves me 3.5mm (dependant on tyre profile) over the original-spec 'Blade tyre. This alone is not enough though.
But, comparing the 120/70 - 17 that I have fitted at present with a 120/70 -16 indicates that I will "lose" 25mm (63/64ths of an inch) which equates to half of an inch at the area of contact - enough to clear the header pipe even allowing for tyre "growth" when hot. Have I got my maths right? - I guess the truth will only be known when I fit the smaller wheel / tyre combo for real !

[Suzukidave]

I think i suggested it before but if you slide the forks up in the triple clamp the amount of the fork travel it makes it very easy to see just how much room you have to work with .

[garry55]

you did Dave, and thats how I know I still need an extra 1/2 inch of clearance

I can't shorten the header pipe any more, and although the tyre doesn't actually touch at what would be full compression, it's mighty close. So I would just like a bit more "breathing" space - just for peace of mind

I am not going to let this damn project beat me..............

[Alan H]

Something like leading link forks to push' the wheel forward a tad might be the way, but really a couple more degrees rake on the steering head. Wonder if any bikes have slightly offset forward forks compared to the steering head?
That would all affect steering characteristics of course, but a couple of degrees would give more clearance between pipe and tyre.

[Suzukidave]

I am not going to let this damn project beat me..............

Seeing your other projects i am sure you will figure this out