Topic: Building of a CB500 classic racer

[Sam Green Racing]

Colin, I'm no expert on the lubricaion systems of these bikes but it's still the best bet that the number 5 shell moved a little prior to closing the cases.
The fact that the tensioner failed as well could just be a coincidence.
We'll never be sure what caused the carnage but wish Rene and Yrjo better luck for next season.

Sam.

[turboguzzi]

guys, dont the bearing caps have that little bent part exactly so the cases prevent them from turning? that means that even if bearing cap was displaced a bit, the cases pressure on the tab will seat it back in the right place....

TG

[Sam Green Racing]

Technicaly that's what should hapen Yo but I have seen this happen twice.

Sam.

[scottly]

hei rene

too bad.... hope that next year goes better, you will sure know more about cb500 motors now

your two problems seem unrelated, unless the little piece missing from the tensioner went inside the motor.

can recommend the hornet 600 tensioner i am using, its so much sturdy than stock.

I know your friend had good reliability with the same motor, but maybe he has also the experience of running it for a few seasons? What I am trying to say is that maybe you could take a step back to a more standard motor that maybe will casue less "surprises".

TG


  

Hi Yossef,

I couldn't wait to open the engine after my holliday , so I did it this afternoon.
And as I expected the crankshaft and bigend bearing are damaged , particular on the right side.
One of the conrods has became blue at the bigend.
Although there was enough oil at the bearings when I opened the engine , there must have been a failure in the oil supply.
The tuner thinks that this happened after the rebuild with the new gear , when starting the engine again.
Although I started the engine after the rebuild on the paddock starter without ignition on , to pump the oil all around and after a few seconds starting with ignition on.
There must be left a lot of air in the oil gallery's and oilcooler hoses he thinks and then you have no lubrication for a while which can cause damage.
This winter we had already planned to inspect and change al the crankshaft and bigend bearings if neccessary.
Our friends bike is indeed more reliable then ours with the same specs , we interchange al the experience with the engine to each other , we have no secrets , I think it is just bad luck we had.
I have n't found the missing piece of the camchaintensioner maybe this missing piece is grinded and has caused the damage.

The damage to the bearing in the first picture looks like lack of lubrication to me...

[Howell]

Yesterday back from a two week holliday to France and Spain.
I find this in my mailbox , the new Davies Motorsport chassis for the CB500/4
Weight 7,4 kg

[turboguzzi]

Yesterday back from a two week holliday to France and Spain.
I find this in my mailbox , the new Davies Motorsport chassis for the CB500/4
Weight 7,4 kg

you must have a very big mailbox if that one fits inside

so, rene, replica of what frame is that frame?

TG

[iomtt9]

tg its a 500/4 frame

[turboguzzi]

tg its a 500/4 frame

pressed sheet spine tube and all?

[Howell]

Yesterday back from a two week holliday to France and Spain.
I find this in my mailbox , the new Davies Motorsport chassis for the CB500/4
Weight 7,4 kg

you must have a very big mailbox if that one fits inside

so, rene, replica of what frame is that frame?

TG

It's from Davies Motorsports :
http://www.daviesmotorsport.com/
 http://forums.sohc4.net/index.php?topic=65180.msg873278#msg873278

This is what they wrote to me:
  Hi Rene, we are at the Stafford classic bike show with it this w/end I will take a lot of photos
and send them to you on monday! the frame weighs only 7.4 kgs and we do everything for
it forks with cartridge conversion, rear shocks fully adjustable only 1kg each, tank, seat,
everything for rolling chassis! please find photo I took last week before it was finnished
and I will send new ones on monday.
   regards John.
 
 

[Sam Green Racing]

I'll look out for that one Rene.

Sam.

[turboguzzi]

I'll look out for that one Rene.

Sam.

ask how many $$$$

[Howell]

I'll look out for that one Rene.

Sam.

ask how many $$$$

Honda 500/4 Replica Chassis and Swing Arm  Made with the latest Reynolds 631 tubing  £1850
http://www.daviesmotorsport.com/framekits.html

That's about € 2100,=

[Howell]

I'll look out for that one Rene.

Sam.

Oké Sam

[Sam Green Racing]

I'll look out for that one Rene.

Sam.

ask how many $$$$

That's just the frame and swinger Yo, not a roller

Sam.

[Howell]

Dutch build CB500 in the 70's.
Dry weight 135 kg.
60 Hp at the rearwheel.
4 Dell Orto carbs 27mm.
Look a like Seeley frame.
Bike was completely destroyed during a race against a tree , rider broke his legs.

[Howell]

Some more pictures I received today from Davies Motorsport about the CB500/4 frame and the mailtext:

hi Rene, Here are a few photos from the show this w/end, we had a excellent show and took 6 orders (deposits paid) and 3 more
coming back to us this week. The frame is a honda replica made with new Reynolds 631 tubing, Frame weighs only 7.5 kgs ,
frame kit comes with frame, swing-arm, rear wheel adjusters cost £1850.00 Complete rolling chassis includes everything
less engine & exhausts is £7850.00 or all parts sold separately! Forks are our own 35mm with our cartridge conversion
(as now being used by lots of top riders) Rear shocks (our own) fully adjustable inc lenght adjustment! Yokes are our own
as most of the parts! Complete weight of bike we think will be 125/127kgs. Rene i will come back to you with wheelbase
and steering head angle when I have spoke to Colin for that information. At the moment we are having conrods, slipper pistons
camshafts and lots of other parts made to our spec! we are going for over 70bhp! but reliable! Talk soon.
  Regards John (Davies)

[turboguzzi]

neat toy! 70 hp... i'll wait for the dyno graphs

TG

[bwaller]

Obviously these guys are top shelf, but I'll be interested in the actual finished weight too!

[Sam Green Racing]

Ben took pics at the show but Rene has saved him the job of posting . The frame that they had there was real easy to lift and it was on a shelf at about shoulder height. They claimed 8kg not 7.5 as in your mail from them Rene, there again, what's half a kilo between friends
It looked a real nice job. The frame looked to be welded but the lugs on the swingarm where the shock mounts looked braised. why not braise it all.
Col and his mate both bought one

Sam.

[Howell]

Obviously these guys are top shelf, but I'll be interested in the actual finished weight too!

I am also curious about the weight , it seems to me very light.
And how is the handling , did they test it already on the track ?
Our bike is 151 kg with oil and fuel , the frame and swingarm are 17 kg.
So they save on the frame and swingarm about 9 kg.

[Howell]

hei rene

too bad.... hope that next year goes better, you will sure know more about cb500 motors now

your two problems seem unrelated, unless the little piece missing from the tensioner went inside the motor.

can recommend the hornet 600 tensioner i am using, its so much sturdy than stock.

I know your friend had good reliability with the same motor, but maybe he has also the experience of running it for a few seasons? What I am trying to say is that maybe you could take a step back to a more standard motor that maybe will casue less "surprises".

TG


  

Hi Yossef,

I couldn't wait to open the engine after my holliday , so I did it this afternoon.
And as I expected the crankshaft and bigend bearing are damaged , particular on the right side.
One of the conrods has became blue at the bigend.
Although there was enough oil at the bearings when I opened the engine , there must have been a failure in the oil supply.
The tuner thinks that this happened after the rebuild with the new gear , when starting the engine again.
Although I started the engine after the rebuild on the paddock starter without ignition on , to pump the oil all around and after a few seconds starting with ignition on.
There must be left a lot of air in the oil gallery's and oilcooler hoses he thinks and then you have no lubrication for a while which can cause damage.
This winter we had already planned to inspect and change al the crankshaft and bigend bearings if neccessary.
Our friends bike is indeed more reliable then ours with the same specs , we interchange al the experience with the engine to each other , we have no secrets , I think it is just bad luck we had.
I have n't found the missing piece of the camchaintensioner maybe this missing piece is grinded and has caused the damage.

Last week I removed the conrods from the crankshaft.
We have to make a new lighthened crankshaft and conrods because the bigends are heavy damaged.
The conrods are all blue and all out of round.

[MaaseyRacer]

Yesterday back from a two week holliday to France and Spain.
I find this in my mailbox , the new Davies Motorsport chassis for the CB500/4
Weight 7,4 kg

What size rims and tires are you running on that frame?

[turboguzzi]

hei rene

too bad.... hope that next year goes better, you will sure know more about cb500 motors now

your two problems seem unrelated, unless the little piece missing from the tensioner went inside the motor.

can recommend the hornet 600 tensioner i am using, its so much sturdy than stock.

I know your friend had good reliability with the same motor, but maybe he has also the experience of running it for a few seasons? What I am trying to say is that maybe you could take a step back to a more standard motor that maybe will casue less "surprises".

TG


  

Hi Yossef,

I couldn't wait to open the engine after my holliday , so I did it this afternoon.
And as I expected the crankshaft and bigend bearing are damaged , particular on the right side.
One of the conrods has became blue at the bigend.
Although there was enough oil at the bearings when I opened the engine , there must have been a failure in the oil supply.
The tuner thinks that this happened after the rebuild with the new gear , when starting the engine again.
Although I started the engine after the rebuild on the paddock starter without ignition on , to pump the oil all around and after a few seconds starting with ignition on.
There must be left a lot of air in the oil gallery's and oilcooler hoses he thinks and then you have no lubrication for a while which can cause damage.
This winter we had already planned to inspect and change al the crankshaft and bigend bearings if neccessary.
Our friends bike is indeed more reliable then ours with the same specs , we interchange al the experience with the engine to each other , we have no secrets , I think it is just bad luck we had.
I have n't found the missing piece of the camchaintensioner maybe this missing piece is grinded and has caused the damage.

Last week I removed the conrods from the crankshaft.
We have to make a new lighthened crankshaft and conrods because the bigends are heavy damaged.
The conrods are all blue and all out of round.

Rene, seeing how these rods look it begs to be asked if you checked the oil level before you started the engine...   

it all might be related to the little piece of tensioner blade that broke, but to me it looks like plain lack of oil. even a badly scored pump rotor would still supply some oil to the bearings.

There is always next year...

[Howell]

Hi Yossef,

After the rebuild with the new gear , I put new oil in it (3.5 ltr) , and before installing the crankcases together I sprayed oil over the crankshaft bearings and between the conrod bearings.
I started the bike at home on the paddock starter without the ignition on , to pump the oil trough the engine.
After halve a minute I started it with ignition on and let it run for about 5 minutes.
For the first practice of the last race , we warmed up the engine during a ten minute waite in the paddockstreet and it sounded good then.
The tuner told he has seen this damage before in one of his own tuned engines , there was not enough oil flow to the bearings caused by air in the oilsystem.
We have no other explanation for the damage.
He says now , when you have drained the oil after the engine was opened and fill it again, always remove the oilpass plug on the left side under the crankshaft, then starting without ignition on till the oil comes out the plug.
So you are sure that the oil is everywhere in the engine.
Nexs time we do it this way.

[Howell]

Yesterday back from a two week holliday to France and Spain.
I find this in my mailbox , the new Davies Motorsport chassis for the CB500/4
Weight 7,4 kg

What size rims and tires are you running on that frame?

Front: 1.85 x 18 rim with Avon AM20 90/90-18
Rear : 2.50 x 18 rim with Avon AM23 130/65x 18 cantilever