December 2017Post
Wakefield park the engine was reported
to have lost power, so Ivan did some
prelim investigating and found one
tappet nut had come loose. So loose in
fact that it fell off, creating a little
trouble on a short trip across the
rocker box. Luckily not much damage was
caused and all the pieces were easily
retrieved from the engine. Stacy had
also reported the bike was jumping out
of gear, so a little more investigating
was done. It was
decided that a “freshen up” was
probably a good idea, so the motor has
been completely stripped down. A broken
selector pin in 1st / 2nd selector fork
was found so this was fixed, but while
looking at the gear set, I noticed that
3rd on the main shaft
wasn’t moving far enough into
engagement. This has been remedied by
grinding .035” from one side of the
gear, and re-shimming the other side. We
now have full engagement of the dogs.
Hopefully this solves the problem. All
the spares we need have been ordered
from Geoff XS, these include, a new set
of piston rings, valve guide seals, and
the required gaskets to re assemble. Next
race meeting is the Island Classic in
January. Do yourself a favour and make
your way down and have a look. More
fantastic classic race bikes than you
can poke a stick at , and of course our
club racer. Cheers, Nick McGinn. p.s the photo is the extra shim need to move the gear across after grinding. It’s the one the scriber is pointing at. Other good news ,Stacy reported clutch to be “perfect”!!!!! (thank God) November 2017A new Tachometer has been donated to the club racer and will be fitted to the bike in time for the Aussie titles. The Scitsu tacho was the one Ivan specified and is the same as the one fitted to his racer. It was donated by Terry Gliddon. All we need to do now is fabricate a mounting bracket so Ivan can fit it to the bike before racing commences at Wakefield. Hopefully this will help Stacey have a successful weekend. |
October 2017The Mount Tarrengower Hill Climb was run on the weekend of the 14th and 15th of October with Stacey competing on our club racer and winning the bike section with the fastest time up the hill with a time of 43.9 seconds. This time was only a few tenths off the fastest ever time recorded for a bike. Stacey had some bad luck with the failure of a $12 part causing her to abandon her third run or she might have taken the title of fastest time ever for a bike. The part that failed was the radial bearing behind the clutch causing the nut holding the clutch onto the gearbox shaft to come loose locking the clutch. Nick McGinn has now repaired the problem so the bike is ready to compete at the Australian road racing championship at Wakefield park raceway in November. Thanks Nick, great job. |
July 2017Stacey has just signed a deal with Hi-Tec Oils and as this involves us we will be getting some oil product for future oil changes in our racer. Hi-Tecs technical department has assured us that the oil that is being supplied is equivalent to the Castrol Activ 4T we have been using to date and Ivan has decided to go with them as Stacey will be supplying us with that product as part of that deal. June 2017After the major rebuild the bike went Winton and in Stacey's hands cleaned up the opposition taking out the P4Unlimited class and also winning the Ken Lucas Cup. April 2017Following the Barry Sheene Festival of Speed and the Victorian Road Race Titles, where the bike performed very well incidentally, it was noticed that a crack had started to appear in the upper crankcase. As
you can clearly see in the picture it
has cracked in the top case just in
front of the rear engine mount and to do
the job properly it will have to be
welded inside and out to make sure it
does not reoccur. While this is being fixed John Chambers who has the rolling chassis at his workshop will do some minor touch ups on the frame to make it look pretty again but also the check it over for any problems that might be evident. Here is the motor all apart to repair the cracked crankcase at Nick’s place, he has transposed all the internals into another set of cases we had that were donated so we’ll use them and get the others repaired for spares. While it was apart Nick noticed the cush drive springs in the back of the clutch basket had broken again. I had a spare set so I sent them up for Nick to use. While he was checking out everything he noticed the bearing bush in the primary drive gear was a little tight so he machined .002” off the bush and the clutch spins nicely now. This is the bush previously described which was too tight and may be the cause of some of the clutch dragging issues that have plagued us. We will soon see when it’s all together again. When I last spoke to nick the motor was well on the way to being together again as evidenced by the pic he sent me, just the head to go and it will be all but finished. The
cush drive springs have yet to fitted
but that begs the question do we use the
buffer blocks or go ahead and just fit
all new springs? The buffer blocks
restrict the rotary motion of the
primary drive gear which compresses the
springs and the theory is if you can
prevent the springs from binding it will
stop them from breaking. We have never
used the buffer blocks before because
Ivan doesn’t use them in his racer so
we decided to follow his lead and not
fit them either but now it seems it
might be beneficial to try them. Ivan
might not have the problem because he
has a different riding style to Stacey
but will only know if we give it a try
and see what happens. Notice
the webbing inside the crankcase on this
early model compared to the heavier
webbing on the later set below. This
may be the reason we got some cracking
in our crankcase and the reason why the
factory added some extra heavier webbing
on the later models. Interesting theory.
Thanks
to Nick and all involved in getting our
racer back on track. March 2017International
Festival of Speed 2017 The International Festival of Speed or as we affectionately call it the Barry Sheene was run on the weekend of the 23rd – 26th of March at the Sydney Motorsport Park Eastern Creek Venue with several XS650’s in attendance. The club racer was there of course with Stacey Heaney aboard and Ivan Hoey was also there with his championship winning bike and last but not least Mark Peatman’s team FCR bike was also there with ex club member Colin Waltho aboard. Heading
out for the last race Stacey
also rode a Honda CB125 and a Suzuki
T500. She also rode a Royal Enfield in
practice but the class was cancelled so
she then rode the club racer in the P4
750 class as well to finish the weekend
with a 4th place result in
that class. The Races Friday - P4 Unlimited Leg 1
- Stacey started the day with a fastest
lap on lap 2 with a 2:07.906 Ivan did
not appear in the results for this race.
P4
750 Leg 1 - Ivan started with a fastest
lap on lap 2 with a 1:54.946 followed by
Stacey with a fastest lap on lap4 with a
2:00.922 and Colin following them with a
fastest lap on lap2 with a 2:07.757 but
received a 10 second penalty for a jump
start. Saturday - P4
Unlimited Leg 2 - Ivan started this race
with a fastest lap on lap 3 with a
1:53.588 and Stacey following him with a
fastest lap on lap3 with a 1:58.064
P4
750 Leg 2 - Ivan again lead the way with
a fastest lap on lap5 with a 1:54.397 with
Colin following him with a fastest lap
on lap 4 with a 2:01.954 and Stacey
following them with a fastest lap on lap
5 with a 2:03.405
P4 Unlimited Leg 3 - Stacey was
alone again in this race and managed to
do a fastest lap on lap 5 with a
1:57.429
P4 750 Leg 3 - Ivan lead the way
again with a fastest lap on lap 3 with a
1:52.590 followed by Stacey with a
fastest lap on lap 4 with a 1:57.701 and
Colin following with a fastest lap on
lap 5 with a 2:02.553 Sunday - P4 Unlimited Leg 4
- Stacey finished this leg with a
fastest lap on lap 4 with a 2:00.572 and
Ivan DNF
P4 750 Leg 4 - Ivan bounced back
to lead the XS’s with a fastest lap on
lap 6 with a 1:53.563 closely followed
by Stacey with a fastest lap on lap 3
with a 1:55.967 and Colin DNF
P4 750 Leg 5 - Stacey again lead
the XS’s with a fastest lap on lap 3
with a 1:58.602 followed by Colin with a
fastest lap on lap 5 with a 2:02.333 and
Ivan DNF The Results L –
R Ivan
Hoey (5) Stacey Heaney (162) Colin
Waltho (110). Well done to all
our club members involved this weekend. Just a reminder
for all visitors to the track, don’t
touch the bikes unless you are asked to
help. If you visit make sure you don’t
get in the way. The riders do appreciate
your support but they have to focus on
what they are doing so please keep that
in mind. After
a successful weekend of racing at the
Island Classic at Phillip Island the
bike was transported to John Chambers’s
workshop awaiting Nick McGinn’s
attention as the new maintenance person
when the bike is in Victoria. Nick
wasted no time in servicing the bike and
reported a few things to fix. Firstly
one of the carburettor manifolds was
found to be cracked and will need to be
replaced, Ivan went to Gowanloch’s and
bought some Del Orto (Malossi) manifold
rubbers to replace to torn Mikuni
manifolds. Nick has offered to make some
alloy manifolds to fit the new tubes
which connect the carburettors to the
manifolds and have a filler to make the
transition smooth from venturi to port. Gowanlochs supplied replacement manifolds. Nick
made up some new inlet manifold spigots
to mount the carbs incorporating the
spacers previously used to increase the
length of the inlets to nullify the
effect of reversion. |
February 2017
Brembo brakes now fitted to the club racer with new brackets welded to the forks and safety wired and ready for action.
Third gear dogs in bad shape have now been replaced
During this strip down it was also noticed that the crankshaft seal was coming out as the circlip had not been installed. This was potentially very dangerous because of the possibility of oil spewing everywhere had it come out completely. We know the circlip was not fitted originally because it had to be
modified or it couldn’t be fitted. The front sprocket had also been installed backwards causing it to rub on the bearing seal holder and also cause a misalignment of the chain. This has never been changed and has probably raced like this all year. The only sprocket change was for Tasmania when the stock primary drive gears were used so a stock 34 tooth rear sprocket was fitted along with a new chain supplied by Stacey and fitted at the track prior to racing by Mark. This went unnoticed until the motor was removed to inspect the gearbox. It has now been fixed. John Chambers questioned the validity of this claim that the sprocket was installed backwards and offers this explanation. Based
on the assumption that the club racer
does not have a bent frame and that the
rear wheel spacers are stock and correct
length: 1.
The front sprocket (stock
530) is mounted hard up to the drive
shaft sleave which in turn is mounted
hard to the drive shaft bearing, which
in turn is mounted in a fixed location
in the engine cases. 2.
The sleave external face
is the same face as the rear wheel
sprocket mounting surface. 3.
For this purpose lets call
these faces “zero” 4.
The stock drive shaft
sleave protrudes past the stock oil seal
3mm, but as we have the easy access
aluminium inserts that carry the oil
seal, the distance from this aluminium
external edge is 2.6mm. (this aluminium
insert is also locked in the grooved
recess used by the stock oil seal and so
cannot protrude any further.) In
saying, we still have 0.4mm clearance to
the stock sprocket. 5.
During recent re-assemble
of the motor there were no scratch marks
or wear marks visible the aluminium
carrier. I also check these measurements
on another motor to confirm the race
bike was not different for some reason. 6.
Zero is maintained. For the benefit of members; it
should be pointed out that the sprocket
was actually fitted correctly. Unless when fitting the alloy seal carriers: it specifies that a 520 sprocket (in reverse) and chain should be used. Which I am sure it does not. The
club racer whoever is fitted with a 520
chain which uses a stepped sprocket. One
face being flat and the other having a
3mm step to maintain standard sprocket
thickness so the lock tab and lock nut
work correctly. This
does not change
the
“Zero” surfaces. This is how it was
install to maintain the correct line. The
idea that the sprocket be reversed was
to give more clearance to the aluminium
seal carrier. Instead of the 0.4mm
clearance it now has 3.4mm. This also
gives better clearance for grit and
grime. It also gives a larger flatter
surface for the lock washer to press
down on but not much. I
questioned this with Ivan and he then
informed me that the rear wheel sprocket
had been packed to allow for this.!!!!
And to give the rear tyre additional
clearance of the chain. I
then ask you all why accuse or point out
that the front sprocket was installed
incorrectly if you don’t tell us that
these changes have been made. This I am
assuming happed in Tassie when the rear
sprocket was change and refitted as
these spacers where not on the bike at
Phillip Island when the previous
sprocket change was made. These spacers
that have been fitted are only washers
of 1.2mm and still fall short by 2.2mm
to bring us in to a line of “Zero plus
3.4mm” I
have spoken to Nick and he is prepared
to machine a correct offset (based on
the straightness of the wheel, engine
alignment. Should be 3.4mm plus or
minus. It maybe that
the 1.2mm washers are enough if things
are actually not in correct line.
These fit nicely under
the tank. A new fibreglass seat has also been supplied by Mark Peatman as the old one was always cracking and needing repair and the new seat allows us to throw away those troublesome number plates that were always cracking too. So now we can put the numbers on the side of the seat cowling instead. I’ll put some pics up when it is mounted to the bike. The Fairing tank and seat are almost ready to paint in the new red and white colour scheme. Another club member,
Nick McGinn, has stepped up with an
offer to service the racer when it’s
in Victoria. If you have ever seen any
of Nick’s bikes you will know how good
this offer is, Nick’s bikes are works
of art and his attention to detail is
first class. On behalf of the club
members I want to thank everyone who has
donated their time and parts to make
this happen especially Ivan Hoey, Mark
Peatman and Geoff Bamford and look
forward to seeing this racing in 2017. Stacey Heaney has
indicated she would like to race the
bike at the Barry Sheene this year and
Steve Hobbs has already offered to not
only pit crew for her but to also offer
accommodation to her and her father Des
and boyfriend Caillin for the weekend. As you can see the bike
looks Fantastic in its new colours. Stacey should be more
than happy to be seen on such a great
looking bike and I have every confidence
that it will perform as well as it
looks. |
2017 JanuaryWith the new year comes a new approach for the club racer, this year we have some sponsors which makes a huge difference to the way we will go racing. Over the Christmas break we made a number of significant changes to the racer. Probably the most noticeable is the change of paint scheme. Also changed was the braking system to Brembo front calipres. With this change to Brembo calipres came the need to change the master cylinder from the current bore to one with a smaller bore to prevent the wooden feeling when the brakes are applied. The explanation and chart below is taken from our old friend Mike Morse's website at Vintage Brake in the USA. |
While attending
Vintage Days West, and thoroughly
enjoying it, I was reminded that many of
the people I had occasion to talk to,
lacked an understanding of the
importance of master cylinder to wheel
cylinder ratios. This critical ratio is
of paramount importance in determining
"feel". It has been my
experience that there is a "sweet
spot" in the range. I like ratios
in the 27:1 range-2 finger power brakes,
feeling some line and/or caliper flex.
23:1 is at the other end of the
spectrum-firm. Ratios lower than 20:1
can result a feel so "wooden"
as to have a toggle switch effect:
nothing happens until the wheel locks.
Disc and wheel diameters must be taken
into consideration. A 10 inch disc
working against an 19" wheel just
doesn't have the leverage ratio that a
13 inch disc working a 17" wheel
does. The hand lever ratio counts too:
witness the adjustable master cylinders
from Lockheed and Brembo. For 2 piston opposed calipers, I like ratios in the 27:1 range, feeling some line and caliper flex. For a firmer lever, use 23:1. I think ratios lower than 23:1 produce a lever feel so "wooden" as to have little, if any feel. Combine "low" leverage ratios with sticky pads, and unpredictable lockup is the result. The high effort required at the lever also results in undesired input to the bars. Single piston calipers are much happier in the 14:1 to 12:1 range. Disc and wheel diameters, as well as hand lever ratios, must be considered. Front Master Cylinder to Wheel
Cylinder |
In our case we have two Brembo calipres with two 38mm pistons each, so if we look at the chart at the line 38mm(4) and read the description above it tells us we need a master cylinder that gives us around a 27:1 ratio for best feel then we can see the master cylinder bore size should be between 14mm and 15mm. As Mike states in the preamble the wheel size and rotor size must also be taken into consideration and as we use a 18" front wheel in the racer and a few millimetres have been removed from the diameter of the rotors to allow a proper fit for the calipres we will be using a 16mm master cylinder the same as Ivan's bike. The next job is to go and find one. |