CBX Racing

CBXs, new bikes, old bikes, cars, trucks, general chat, off topic, this is the place to post it.
Warwick Biggs
Power Poster
Power Poster
Posts: 384
Joined: Tue Nov 03, 2015 10:23 pm
Location: Australia
Location: Australia

Re: CBX Racing

Post by Warwick Biggs »

Roberto Crepaldi (Ferrari agent).

Warwick Biggs
Power Poster
Power Poster
Posts: 384
Joined: Tue Nov 03, 2015 10:23 pm
Location: Australia
Location: Australia

Re: CBX Racing

Post by Warwick Biggs »

I wish things would slow down a bit. The world is spinning too fast and I just need to step outside for a minute to catch my breath. And why is technology always working against me? Merde!

More pics from the Biggs archive have emerged from the dungeon and may find their way to the surface, altho' Einstein was not entirely convinced by gravity so who can tell?

Warwick Biggs
Power Poster
Power Poster
Posts: 384
Joined: Tue Nov 03, 2015 10:23 pm
Location: Australia
Location: Australia

Re: CBX Racing

Post by Warwick Biggs »

Of course that evening would never have happened if Milligan hadn't screwed up the bookings. Hugh hailed from New Zealand. the land of the long white cloud and the birth place of many a mad motorcyclist. Aeteoroa. Milligan paid for it tho' when we visited those high places a while later he lent me his Hinkley Trumpy and then complained when I returned it with the sidestand sharpened. How could you avoid that with all those sinuous roads up and down the mountains and glaciers. He was lucky to get the bike back in one piece!

Warwick Biggs
Power Poster
Power Poster
Posts: 384
Joined: Tue Nov 03, 2015 10:23 pm
Location: Australia
Location: Australia

Re: CBX Racing

Post by Warwick Biggs »

high places
You do not have the required permissions to view the files attached to this post.

Warwick Biggs
Power Poster
Power Poster
Posts: 384
Joined: Tue Nov 03, 2015 10:23 pm
Location: Australia
Location: Australia

Re: CBX Racing

Post by Warwick Biggs »

The shims now have been made up and the head reassembled with the stock clearanes ready to be re-attached to the body of the motor. Still having trouble getting new O rings for the extended sump. Comms with TIMS not good and issues with international freight apparently. Now trying to find a generic set of O rings that will fit.

This is the last remaining impediment to getting the lump back together for the National Championship in November. I'm also not entirely happy with the siliconing of the split CR carb rubbers but I absolutely refuse to pay nearly $1K for a new set (assuming the resumption of airfreight). That amount of money could support a family for a year in many parts of the world and is far too much for 6 rubbers. I will try wrapping them in Gladwrap as well.

Does anybody know of a mechanical grade of Gladwrap, I wonder? The rubbers get pretty hot.

User avatar
Syscrush
ICOA Member
ICOA Member
Posts: 1283
Joined: Fri Sep 14, 2012 2:29 pm
Location: Toronto, ON
Location: Toronto, ON

Re: CBX Racing

Post by Syscrush »

Warwick Biggs wrote:
Sun Jun 07, 2020 7:27 pm
Does anybody know of a mechanical grade of Gladwrap, I wonder? The rubbers get pretty hot.
The standard issue upgraded cling film would be thicker for use in shipping (used for wrapping skids of material). It looks like the stuff you get in the grocery store is OK for boiling temps but not much higher.
Phil in Toronto
A cool guy deserves a cool bike, a dork needs a cool bike...
Pics of Perry, my '79.

Warwick Biggs
Power Poster
Power Poster
Posts: 384
Joined: Tue Nov 03, 2015 10:23 pm
Location: Australia
Location: Australia

Re: CBX Racing

Post by Warwick Biggs »

Interesting. Roly has measured his Beast running at 280 degrees so if Gladwrap is good for only 250 then I might need to wrap it in alfoil to get it's utility up to 350???

My thinking was any melted glad wrap would be sucked into the splits and possibly seal them. Or, it keeps going into the motor and it goes bang! Maybe I should just stick with the high temperature silicone but it tends to dissolve in gasoline.

Hmm. Does anybody have any other suggestions besides new rubbers?

Warwick Biggs
Power Poster
Power Poster
Posts: 384
Joined: Tue Nov 03, 2015 10:23 pm
Location: Australia
Location: Australia

Re: CBX Racing

Post by Warwick Biggs »

Seems not. Oh well, I guess most people have more important things on their minds, including Bill at TIMS. He has gone AWOL with my gasket order. Not to worry as we can make them here or make do. The head is going back on and the National Championship has been moved forward to 12 -15 November to allow some re-jigging of the Oz Superbike championship dates due to the covid disruptions.

That leaves even less time to prepare and find sponsors. Tomorrow week we should be back on the track for practice. The CBX won't be ready so I will take the GSXR750 that now has a shark fin fitted and I've drilled and lock wired for racing. I've also patched the belly pan and repainted it after wearing thru' both sides. It has to hold at least half a litre of spilt oil in lieu of a catch tank. In any event I was surprised to be dragging the belly so have upped the compression on the rear well past sag and dropped the front forks to flush with the triple clamp and we will see how that goes.

Those of you who have followed Roly and the Beast will have noticed that his bikes have not been on the track since 2016 after Trev's crash at the Island. I'm trying to encourage him back to the fray in November with the idea of a CBX Cup with a special trophy for the fastest CBX. It might help if there was some support for the concept from the CBX community. I know its a lousy time right around the world but can we get some priorities straight here? We are talking CBX racing!

User avatar
Syscrush
ICOA Member
ICOA Member
Posts: 1283
Joined: Fri Sep 14, 2012 2:29 pm
Location: Toronto, ON
Location: Toronto, ON

Re: CBX Racing

Post by Syscrush »

Warwick Biggs wrote:
Fri Jun 12, 2020 10:45 pm
Hmm. Does anybody have any other suggestions besides new rubbers?
This guy shows using heat shrink tubing, might be worth a shot:



He specifically states that it's OK with the exposure to heat and gasoline. It looks tidy and would be a quick operation.
Phil in Toronto
A cool guy deserves a cool bike, a dork needs a cool bike...
Pics of Perry, my '79.

Warwick Biggs
Power Poster
Power Poster
Posts: 384
Joined: Tue Nov 03, 2015 10:23 pm
Location: Australia
Location: Australia

Re: CBX Racing

Post by Warwick Biggs »

Thanks Phil. I will give it a shot. I did think of heat shrink but wasn't aware you can get such large diameter heat shrink tubing as I've only ever used it on electrical fittings and I had doubts about resilience to heat and gas. I will post results in due course.

I'm getting close to re-fitting the head but for an abundance of caution would like to check piston to valve clearances b4 starting the motor. My cams are modified by removing meat from the baseline and some people have suggested the stock 0.15 mm shim clearance is too tight for this configuration. I also had to re-seat some valves and am replacing a composite head gasket with a copper gasket. Personally, I can't see a problem providing the cams are set up correctly but just to be on the safe side, is there some way of turning the motor over by hand and checking without having to pull he head back off to see if there are any kiss marks?

Warwick Biggs
Power Poster
Power Poster
Posts: 384
Joined: Tue Nov 03, 2015 10:23 pm
Location: Australia
Location: Australia

Re: CBX Racing

Post by Warwick Biggs »

While the CBX brains trust is cogitating on how to test piston to valve clearance on a modified CBX I thought I would post another CBX pic whilst acknowledging it is from the 2009 Australian Motorcycle News Yearbook for 2009.

Roly's 'Beast', voted "Crowd Pleaser of the Year" in the hands of Mick Dibb. I'm trying to convince Roly to bring the Prolink Beastess along to the 2020 Championship in November for some demonstration laps with past legends - so far, without much success, I have to say. The Beast is still sadly badly smashed up awaiting restoration in a corner of Roly's work shop.
You do not have the required permissions to view the files attached to this post.

User avatar
Syscrush
ICOA Member
ICOA Member
Posts: 1283
Joined: Fri Sep 14, 2012 2:29 pm
Location: Toronto, ON
Location: Toronto, ON

Re: CBX Racing

Post by Syscrush »

Even if you don't get any kiss marks when turning over by hand, that wouldn't mean you're in the clear. I thought that the prescribed approach is to use modelling clay and measure the squished thickness against a spec. I've never heard of a shortcut that lets you do this without a re&re of the head assembly.
Phil in Toronto
A cool guy deserves a cool bike, a dork needs a cool bike...
Pics of Perry, my '79.

Warwick Biggs
Power Poster
Power Poster
Posts: 384
Joined: Tue Nov 03, 2015 10:23 pm
Location: Australia
Location: Australia

Re: CBX Racing

Post by Warwick Biggs »

A method suggested by Roly is to cut out a 1.5mm piece of soft copper the diameter of the bucket and slip it under the cam lobe. Turn over the motor by hand and if it completes a full rotation without any resistance then you have adequate piston to valve clearance.

Our club ride day, the first serious activity at the track since February, went well. Weather was good altho' chilly and we had close to a full complement with most garages chocka, including at least 2 lap record holders in the expert group. This was good considering that State Borders remain closed to protect SA's virus free status, meaning almost all riders were South Australians.

However, it has to be said that a lot of the riding was a bit ragged with a higher than normal number of pick ups. I found myself drifting thru' corners searching for a gear on at least two occasions and had to take evasive action a number of times as riders came thru' rather too closely in varying degrees of control. As usual, keeping the Suzuki's front wheel on the ground was a constant challenge and the explosive power did not translate into smooth riding or satisfactory lap times. But at least we finished all sessions without any breakdowns or incidents and were quicker at the end than at the beginning.

Yet again, I had a front seat to riders so focused on making a pass as not to be able to make the following corner. I don't know how many times people have to be told that a ride day is not for racing. Social distancing tended to break down a bit too as the day progressed and riders became more excitable and loquacious. Definitely a sign of the stress of months of relative isolation for many.

Hopefully we will have the CBX back together for testing in our next outing and the virus continues to remain at bay. The major source in Oz remains overseas travellers who breach quarantine.

User avatar
Syscrush
ICOA Member
ICOA Member
Posts: 1283
Joined: Fri Sep 14, 2012 2:29 pm
Location: Toronto, ON
Location: Toronto, ON

Re: CBX Racing

Post by Syscrush »

Warwick Biggs wrote:
Sat Jun 27, 2020 8:29 pm
A method suggested by Roly is to cut out a 1.5mm piece of soft copper the diameter of the bucket and slip it under the cam lobe. Turn over the motor by hand and if it completes a full rotation without any resistance then you have adequate piston to valve clearance.
That sounds like a great tip. Glad to hear that you were able to get out on the track again and that there don't seem to have been any mishaps.
Phil in Toronto
A cool guy deserves a cool bike, a dork needs a cool bike...
Pics of Perry, my '79.

Warwick Biggs
Power Poster
Power Poster
Posts: 384
Joined: Tue Nov 03, 2015 10:23 pm
Location: Australia
Location: Australia

Re: CBX Racing

Post by Warwick Biggs »

I haven't tried it yet and he reckons you have to be careful as you complete a rotation because it tends to fly out with some force.

I have found some 80 mm (3") polyolefin heat shrink rubber tubing that is supposed to reduce down to 16 mm. It also has glue on the inside to ensure a secure seal around the carb rubbers I'm told that this is the most durable material but we will have to wait and see how it goes in practice.

A very good feature of our historic rules is that the suspension has to be what was available in the day. In my case this has only meant stronger springs in the stock prolink forks, dropped flush with the top tc, ditching the air assist and modified internal valving. OK, the rake has been modified too but you would be hard pressed to notice any difference from stock, right down to the 4 piston Prolink brake calipers.

Compare this with the multiple adjustable settings on a modern race bike. Typically this involves adjustable length suspenders all round and/or adjustable mounts, adjustments for ride height and offset (affecting rake & trail), adjustable spring preload all round for setting static and rider sag, adjustable slow and high stroke compression damping all round and adjustable rebound damping all round. And these adjustments all inter-relate meaning a change to one often means a change to others. It is almost impossible not to get lost in the almost infinite combinations so, method is essential to avoid madness.

Is it any wonder that modern race teams have a small army of technicians that spend days setting up the bikes for each track and weather/tyre situation. I ended up reversing most of my adjustments on the GSXR track bike over the w/e and am still little the wiser as to the correct solution. But I have recorded all my mistakes. Something else to get my head around that is thankfully absent from the CBX or the NC30.

The next race is slated for 21-23 August and will be the Seniors combining the age of rider and machine into separate classes and a meeting I normally go well in. It could be the next outing for the CBX, fingers crossed.

Post Reply

Return to “Daily Discussion: By, For & About CBXers”