Author Topic: Building of a CB500 classic racer (Read 207606 times)

iomtt9 · « **Reply #250 on:** March 28, 2010, 03:23:20 PM »

I think they are from cb 650 rocker shafts, you have to use the 550 rocker cover because the shafts are locked in with cotter pins, so these then screw into the shaft complete with O ring.

turboguzzi · « **Reply #251 on:** March 28, 2010, 04:32:39 PM »

the regular 500 shafts have 6mm threads at the end to help pulling them out.

all you have to do is put there some rubber seals and press them wit two short 6mm screws and a washer.

TG

Howell · « **Reply #252 on:** March 30, 2010, 01:01:23 PM »

There are two types of covers for the CB500 , the early ones need the end caps to hold the rocker arms in place.
The latest version has four extra bolds to hold them in place , so you don 't need the end caps.
On the no 46 engine picture you see the latest version, our engine the early one with endcaps.
See the parts pictures for the differences.

Howell · « **Reply #253 on:** March 30, 2010, 01:04:18 PM »

Quote from: Howell on March 30, 2010, 01:01:23 PM

There are two types of covers, the early ones need the end caps to hold the rocker arms in place.
The latest version has four extra bolds to hold them in place , so you don 't need the end caps.
On the no 46 engine picture you see the latest version.
See the parts pictures for the differences.

Difference at the rockerarms:

fastbroshi · « **Reply #254 on:** April 04, 2010, 12:49:42 AM »

Are those bolts in the later version or middle of the rocker cover sufficient to hold the rocker shaft? I remember hearing a bit about certain versions of the 500/550 shafts wearing prematurely or failing. Can someone fill me in?

bwaller · « **Reply #255 on:** April 04, 2010, 04:55:14 AM »

The locks do secure the four longer shafts, preventing them from rotating and wearing the rocker cover. This was sometimes the problem with the earlier eight shorter shafts. Like the 750 rocker shafts, when they are prevented from turning any shaft wear is concentrated where the rocker sits, but I don't think there were problems with shaft failure in the 550 otherwise.

Howell · « **Reply #256 on:** April 06, 2010, 12:01:34 PM »

First race 05-04-2010 Assen:

First practice:
13th place , track was halfwet half dry.
Difficult circumstances , many crashes.Riders with broken collarbones and ribbs.
But for the first time a good result.

Second practice:
6th place compleet wet track with heavy rain and wind.
Most riders stopped after 5 laps.
Time was slower than in the first practice.

Raceday:

Dry after two wet days.
In the morning a warmup training , every body was going faster also my son.
But he is still searching to his own limit and that from the bike.
Assen is a very fast track with many high speed corners.

Race:

Ended in the warmup lap , a lot of noise in the engine , he stopped immediate.

This morning I inspected the engine and again a inletvalve has stucked in the valveguide.
Further no damage.
Same problem as before ?

turboguzzi · « **Reply #257 on:** April 06, 2010, 12:56:54 PM »

indeed!

It might have got stuck there because it got slightly bent....

So a few questions need to be asked.

do you see any contact signs in the other pistons crowns?

what sort of piston to valve clearance are you running?

Is the cam well degreed?

Does it look like the cam and valves get good oil supply?

If you are running valve stem seals, maybe try without them for better lubrication?

The inlet valve shouldnt get hot enough to seize in the guide.....

Is the cam tensioner really good? on upshifts, when the engine is slowed down suddenly, the inertia of the cam will give the tensioner a big whack, if its not working well, the timing gets advanced and the inlet valve might hit the piston.

I know you have a pro engine builder but something is not OK (but you know that already)

Take it easy, results will come!

TG

GStarIndustries · « **Reply #258 on:** April 07, 2010, 10:28:54 AM »

What type of seat are you running in the first pics? I like!!!

Howell · « **Reply #259 on:** April 07, 2010, 12:19:27 PM »

Quote from: turboguzzi on April 06, 2010, 12:56:54 PM

indeed!

It might have got stuck there because it got slightly bent....

So a few questions need to be asked.

do you see any contact signs in the other pistons crowns?

what sort of piston to valve clearance are you running?

Is the cam well degreed?

Does it look like the cam and valves get good oil supply?

If you are running valve stem seals, maybe try without them for better lubrication?

The inlet valve shouldnt get hot enough to seize in the guide.....

Is the cam tensioner really good? on upshifts, when the engine is slowed down suddenly, the inertia of the cam will give the tensioner a big whack, if its not working well, the timing gets advanced and the inlet valve might hit the piston.

I know you have a pro engine builder but something is not OK (but you know that already)

Take it easy, results will come!

TG

Hi Tg,

Thanks for all the suggestions , we think the problem is again the clearance between valvestem and guide.
These valve stems are 5,47 mm , stock Honda valves are 5,45 mm.
After the first time problem with a valve , we gave the guides a little bit more clearance but probably not enough yet.

Howell · « **Reply #260 on:** April 07, 2010, 12:22:28 PM »

Quote from: GStarIndustries on April 07, 2010, 10:28:54 AM

What type of seat are you running in the first pics? I like!!!

This a universal caferacer seat, we cut of the sideskirts:http://www.harrievanderkruijs.nl/images/pol103.jpg
http://www.harrievanderkruijs.nl/interest.htm

Howell · « **Reply #261 on:** April 08, 2010, 12:19:35 PM »

Quote from: Howell on April 07, 2010, 12:19:27 PM

Quote from: turboguzzi on April 06, 2010, 12:56:54 PM
indeed!

It might have got stuck there because it got slightly bent....

So a few questions need to be asked.

do you see any contact signs in the other pistons crowns?

what sort of piston to valve clearance are you running?

Is the cam well degreed?

Does it look like the cam and valves get good oil supply?

If you are running valve stem seals, maybe try without them for better lubrication?

The inlet valve shouldnt get hot enough to seize in the guide.....

Is the cam tensioner really good? on upshifts, when the engine is slowed down suddenly, the inertia of the cam will give the tensioner a big whack, if its not working well, the timing gets advanced and the inlet valve might hit the piston.

I know you have a pro engine builder but something is not OK (but you know that already)

Take it easy, results will come!

TG

Hi Tg,

Thanks for all the suggestions , we think the problem is again the clearance between valvestem and guide.
These valve stems are 5,47 mm , stock Honda valves are 5,45 mm.
After the first time problem with a valve , we gave the guides a little bit more clearance but probably not enough yet.

This valve is bend now.

Our friend with the no 46 Honda , now riding with no 5, made a highspeed crash in a fast corner at 110 mph.
He lost the rearwheel.
He was not hurt only the new fairing of his bike was damaged and some small things like footrest and clipon.
We repaired it.
But in the following warmup training he noticed that the power was gone at top.
In one and a half our we changed the engine , he has a spare.
We were just in time for the race.
During the race lying on 5th place , the engine stopped, electrical problem , broken wire from the battery.

bwaller · « **Reply #262 on:** April 08, 2010, 07:35:17 PM »

Too bad Howell, what material are those valves?

I'm glad your friend wasn't hurt...110mph is no easy get-off, low side or not.

Howell · « **Reply #263 on:** April 09, 2010, 10:54:32 AM »

Quote from: bwaller on April 08, 2010, 07:35:17 PM

Too bad Howell, what material are those valves?

I'm glad your friend wasn't hurt...110mph is no easy get-off, low side or not.

We found the problem , sticky stuff around the valvestem and in the guide.In all the inletvalves and guides.
Solved fibreglass from our tank, this stopped the lubrication for the valveguide.
We use a new fibreglass tank with a special tanksealer that must be resistant against modern fuells with ethanol.
Also this says the dutch importer , but this afternoon I find this on the internet:https://helpdesk.kbs-coatings.com/index.php?_m=knowledgebase&_a=viewarticle&kbarticleid=10&nav=0,1

So, don't use fibreglass with modern fuells with ethanol.
We use the new Gulf Challenger with a lot of ethanol in it and this solves the fibreglass.
Now we let make a aluminium tank and therefore the 'old' tank is model.
I hope it is ready for the next race at 24 april at Spa-Francorchamps , our favorit track.

Our friend made a low side fall, sliding on his back.
But by he fall his best engine is damaged, 4 ruined rockers and the cam , probably no lubrication during the long slide with running engine.

bwaller · « **Reply #264 on:** April 09, 2010, 12:24:01 PM »

Even though it will cost you a bit more at least you have the answer to what has been causing the problem, well done.

paulages · « **Reply #265 on:** April 09, 2010, 12:33:22 PM »

Howell-

Sorry to hear about your fiberglass problems. If you're going to order a sealer form the US anyway, I have had good luck with Caswell's product, which is made specifically to bond with fiberglass. An aluminum tank is a nice solution, but certainly pricier. Hope this is the low point of the season!

Paul

kos · « **Reply #266 on:** April 09, 2010, 03:54:46 PM »

I am very surprised that your race organization allows glass (fiber) tanks. Not only do they not like race gas, and I know some say you can coat them, but they can "explode" upon impact and break into pieces. Alloy is the the tank of choice.

Do yourself and or your rider a favour.. get away from the glass.

KOS

Retro Rocket · « **Reply #267 on:** April 09, 2010, 05:08:48 PM »

Does anyone make injection molded fuel resistant plastic tanks like the ones they use in some race cars?

Mick

Howell · « **Reply #268 on:** April 10, 2010, 12:11:37 PM »

Yesterday I send a email to the dutch division of KBS coatings how to use this coating in fibreglass tanks about the contrary decription between them and that of the manufacturer.
Also I mentioned the problem we had by this and the costs.
This morning I got a phonecall from them , they apoligised for that and are willing to pay the costs we made.
They asked to send them a bill about that , so I am curious if they gonna pay it.
Today I was at the guy who would make a alu tank.
But talking about that , it is a lot of work to make a compleet new tank before the next race.
He is doing this as hobby after working time.
We decided to make a alu dummy tank , so the bottom of the fibreglass tank will be removed and under the uppersite comes a small alu box.
Just big enough for 2,5 gallon , we need about 2 gallon during a race.

The guy who will build the tank is a very talented technical person , he build a special Harley Norton Harton: http://www.google.nl/imgres?imgurl=http://i78.servimg.com/u/f78/13/08/08/47/02-01-10.jpg&imgrefurl=http://classicbikes.actieforum.com/show-us-your-project-f1/harley-norton-project-t438-15.htm&h=600&w=800&sz=199&tbnid=gizypCsStsvsUM:&tbnh=107&tbnw=143&prev=/images%3Fq%3Dharton&hl=nl&usg=__xGNZGcnKVFw_KaCoh4kqcFalsLQ=&ei=2cvAS9u0OtKlOPW4iZcE&sa=X&oi=image_result&resnum=8&ct=image&ved=0CCMQ9QEwBw
The tank on this Harton he builded also.

fastbroshi · « **Reply #269 on:** April 10, 2010, 02:24:54 PM »

Wow that is nice work. And look at that drum!!

Retro Rocket · « **Reply #270 on:** April 10, 2010, 05:20:24 PM »

WOW, that Harton is a work of art......beautiful...

Mick

Ricky_Racer · « **Reply #271 on:** April 10, 2010, 06:01:11 PM »

Now that's inspirational!

RR

MRieck · « **Reply #272 on:** April 10, 2010, 08:10:20 PM »

Quote from: kos on April 09, 2010, 03:54:46 PM

I am very surprised that your race organization allows glass (fiber) tanks. Not only do they not like race gas, and I know some say you can coat them, but they can "explode" upon impact and break into pieces. Alloy is the the tank of choice.

Do yourself and or your rider a favour.. get away from the glass.

KOS

Me too.

lordmoonpie · « **Reply #273 on:** April 11, 2010, 02:27:26 AM »

You can still run glass tanks in the UK club race scene too - never understood why but them's the rules. I'm with aluminium tanks all the way and tbh if you get a good one, they can even be lighter than GRP tanks...

Howell · « **Reply #274 on:** April 18, 2010, 11:12:23 AM »

Yesterday my fibreglass/alu tank was ready.
Many thanks to the builder , build in a week in his freetime.
Under the now dummy fibreglass tank is an aluminium tank made with a contents of 2,5 gallon.( 10 liters)
The bottom of the fibreglass tank is cut away for the greater part.
The front part is kept in place to keep the tank in place on the frame and to support the alu tank.
There is also made a new tank filling hole which also fixes the alu tank in the polyester dummy.
So with this tank I hope the valveproblems are gone.
When the fibreglass bottom was cut away you could see the coating was dripped all to the bottem.
Now up to the second race next weekend at Spa - Franchorchamps.
The bike is running again with two new valves and valveguides.

Colin, meet you there.

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Author Topic: Building of a CB500 classic racer (Read 207606 times)