Honda CB450 K5 Cafe Racer.. ish

xb33bsa

New Member
you only broke it not sectioned it looks ok to replace how long ?
i already fully explained why you dont need a breaker
grind them below the surface a bit
the link will come apart almost without help then .......a "motorcycle chain"chainbreaker is for girls,sissies and bicycle chain and is a straightup,waste of your money i have never needed one in the shop .....
always did carried a little beaver tooth when trail riding without a grinder
 

bezugo

New Member
I understood the method for breaking/shortening the chain. I just didn't think long enough about it so I thought it would damage a new chain.
But I see now. The links that will be ground are the ones coming off. Only one actually.

My other question concerned the length of the stock clutch pushrod. Does it go all the way from the clutch cover to the clutch basket on the other side of the engine?
I sure thought so, but looking closely at the broken bits it seems that I only need a bit of rod that is the same length as those two bits.

Maybe it's just me not understanding you, but what do you mean by sectioned instead of broken or sheared? English isn't my first language, but it's hard to come across a word/meaning that I'm not aware of.
 

xb33bsa

New Member
sectioned would be 3 pieces
its not missing a piece you only broke it in 2 in half just put the 2 together get a rough length
the rod is one piece goes all the way through probly 1" to 1-1/2 " short of measuring all the way to the outside of the clutch cover it should show the image exploded in the factory service manual,if you dont have one download one free from the brain collective over at hondatwins.net
you can also see it in exploded view here:
http://www.cmsnl.com/honda-cb450k7-1974-usa_model455/partslist/E++08.html#results
 

bezugo

New Member
Does the clutch pushrod rotate with the clutch basket?

I got a rod with the same diameter, cut it to length and even rounded off the end that goes into the engine.
My doubt is that i only cut a bit of rod to replace the bits that fell out. Assembled everything (new chain, new sprockets) and the clutch works great. I didn't forget the metal ball.

Went for a little drive and now the engine is revving like crazy!!
If i put it in neutral and let go of the clutch it goes back down, but if i pull the clutch lever it revs up immediately. When in gear and moving its even worse.. WTF!?

I didn't touch anything else, but it seems that the clutch is having some influence.

What can it be?

I didn't replace the whole rod because i wanted to try this out first, but i still have enough rod to make one or two extra entire rods.
 

bezugo

New Member


On the upper right side you can see there is a darker section of the rod. That's where mine broke and that is the only part i replaced since the rest of it remained inside.
 

xb33bsa

New Member
bezugo said:
Does the clutch pushrod rotate with the clutch basket?

I got a rod with the same diameter, cut it to length and even rounded off the end that goes into the engine.
My doubt is that i only cut a bit of rod to replace the bits that fell out. Assembled everything (new chain, new sprockets) and the clutch works great. I didn't forget the metal ball.

Went for a little drive and now the engine is revving like crazy!!
If i put it in neutral and let go of the clutch it goes back down, but if i pull the clutch lever it revs up immediately. When in gear and moving its even worse.. WTF!?

I didn't touch anything else, but it seems that the clutch is having some influence.

What can it be?

I didn't replace the whole rod because i wanted to try this out first, but i still have enough rod to make one or two extra entire rods.
what you did was a creative thing that won't work ,but good for you to try it
it needs to be the stock rod 1 piece the ends are hardened as far as i know,try scratching an end with a file
 

xb33bsa

New Member
and yes it rotates if it wants to ,it floats, if you must make your own rod you will need to use drillrod it is commonly available even in brazil i would bet,and comes in all std drill bit diameters , the ends needs to be hardened ,the drill rod is oil hardening i believe,then should be drawn out a bit,and precision ground or machined to correct shape/flatness on both ends
you could also use cr rod and case harden the ends with some casenite the key being perfect straightness and near perfectly shaped ends
 

bezugo

New Member
Ok. So it won't work this way. I'll try getting a stock rod. Didn't you have one?

What I still don't get is why does the engine rev higher than normal now.
I would understand if it revved lower because of added friction from the rod not wanting to rotate, but this??!

By drill rod do you mean a drill bit with the required length? That would be a good way of getting a perfectly straight rod that is very hard.

Oh and by the way, my native language is indeed Portuguese, but not from Brazil. I'm Portuguese and here I should be able to get everything I need. Everything except parts for a classic Honda :(
I buy everything from the UK or US
 

xb33bsa

New Member
bezugo said:
Ok. So it won't work this way. I'll try getting a stock rod. Didn't you have one?

What I still don't get is why does the engine rev higher than normal now.
I would understand if it revved lower because of added friction from the rod not wanting to rotate, but this??!

By drill rod do you mean a drill bit with the required length? That would be a good way of getting a perfectly straight rod that is very hard.

Oh and by the way, my native language is indeed Portuguese, but not from Brazil. I'm Portuguese and here I should be able to get everything I need. Everything except parts for a classic Honda :(
I buy everything from the UK or US
first where are you ? yes i have a rod ok i see portagee i could sell you a good rod for $12c pluss the international first class mail which wont be bad because very light package
drill rod is drill bit specification steel rod in an annealed state in all drillbit diameters ,its just smooth rod ....the clutch pushrod is nort a practical thing to make ,i could make my own i have the tools but i could buy 10 for the time it tyakes
the reving up problem is a completely seperate issue from the clutch
you have an air leak or throttle cables sticking
before you try to figure it out, before a lot of time chasing dead ends start with a complete tuneup ,including valve clearances and timing chain adjust so you have a base to start out with
 

bezugo

New Member
First of all.. thanks for your help. I may still need that rod you have, but in the meanwhile i tried something a little different.

I took out that piece of rod i fabbed and cut it short by 8mm.

Since i can't get the pushrod from inside the engine (magnet didn't work) and i know it rotates with the clutch since i turned on the engine and looked inside...i just put one 8mm ball inside that hole to minimize friction between the two rods.

It works perfectly :)

Still... i was getting the same issue with revving whenever i pulled the clutch. Sure enough, it was the damn clutch cable pushing against the throttle actuator.
It never did that before. So weird..
I just found a way of getting it away and now it works fine.


Also.. another spark plug died on me. It's always the right side plug that dies because the mixture on that side is too rich.
 

xb33bsa

New Member
bezugo said:
First of all.. thanks for your help. I may still need that rod you have, but in the meanwhile i tried something a little different.

I took out that piece of rod i fabbed and cut it short by 8mm.




Then smoothed out the edge



Since i can't get the pushrod from inside the engine (magnet didn't work) and i know it rotates with the clutch since i turned on the engine and looked inside...



..i just put one 8mm ball inside that hole to minimise friction between the two rods.



It works perfectly :)

Still... i was getting the same issue with revving whenever i pulled the clutch. Sure enough, it was the damn clutch cable pushing against the throttle actuator.
It never did that before. So weird..
I just found a way of getting it away and now it works fine.


Also.. another spark plug died on me. It's always the right side plug that dies because the mixture on that side is too rich.

hey you are pretty slick,like i said before the rod is not meant to be spinning with the shaft but it does because it can .it has plenty of clearance to not spin and it is not connected to anything
the only problem with the repair is that you dont have much support for the short piece it looks like it barely goes inside it may work fine but may take out the seal in short order
as far as the plug being sooty it could be ignition related dont assume its mixture until you know the ignition is in good tune
the carb could have a stick slide or a holed diaphram choke plate may be sticking as well
 

bezugo

New Member
New update

I was still having trouble with the clutch. Every time i went for a ride the clutch lever was gaining play just after a few miles. I even got to the point of almost loosing all travel of the lever and almost didn't get home.

I had to adjust it every single time and the only possibility was that the clutch rod was getting shorter.
Sure enough, it was :mad:

So i pulled it all appart and this is what i found

So it was the sphere between the two rod that was eating them away. Especially the part that was still the stock rod since that part is aluminum. If i had known that i wouldn't even had tried what i did.

Now i'm going to replace the whole thing with a single stainless steel rod that i will make myself and while i'm at it, replace the clutch disks aswell.

Anything else i should do while i have it appart?
 

bezugo

New Member
Time for a long awaited improvement. Both wheels are out and are going to get laced with new spokes and rims. New tires aswell.

And since the bike will be on a stand for a few days i took the chance to refurbish the front forks with new seals and oil.

The oil that was in there had a bad colour. I can only imagine how long it was there.

There was also something strange that i only noticed after i had assembled one of the forks..

That little (thick) washer on the bottom of the spring was mounted upside down on both forks.
It didn't look right, but i assembled the first one the same way because thats how it has been for decades. Luckily i was suspicious and looked for the correct way to do it and had to redo the first one.
 

bezugo

New Member
Hello everyone

Only now i've done a compression test. I borrowed the tester from a car mechanic and went home to do it.

It read 143 psi on both give or take. Very similar compression on both cylinders!
Only after i gave the tester back did i remember that the throttle had to be fully open ::)

What difference should it be with throttle wide open? More i would think, but how much more.

She was hot and the choke open.
 

bezugo

New Member
It´s been a while since i posted anything here, but several things were done.

The clutch was sticking bad after the bike got hotter. After disassembly i noticed the culprit was the clutch basket being scored by the discs and plates.
Both the inner and outer basket were ground and sanded smooth and now it is smoother than ever.

I also painted the engine covers black and polished the stator and oil filter cover. Looks much cleaner now.

I took apart both carbs again and used an Ultrasonic cleaner to really make sure they were clean. When assembling i used the stock needle and the stock mixture screw because i have always suspected the ones that came with the rebuild kit (from 4into1) were slightly different. Also changed the main jet from 145 (stock) to 150 which also came with the kit but have been lost and i recently found them.
New UNI foam filters went where there were cheap pods.

Now the mixture screws actually do something!! Not sure if it is just because the aftermarket ones are not suited for the bike or if it was due to the ultrasonic cleaning.

The bike idled right away with both throttle flaps completely closed. No need to adjust the idle right away. I did it afterwards just for fine tuning, but before she would never hold idle unless i screwed in the idle screws a couple of turns.

I was feeling very confident that the not revving past 5k rpm was solved, but no :( It is exactly the same as before.
It pops and almost seems to backfire if i apply full throttle but does not revv any higher.

I´m lost. What now. Advance? Bigger jets?

I live at sea level.
 

bezugo

New Member
New update.

Went over the advance mechanism again and while it seemed to move freely i took it apart, cleaned it and oiled it.
Put it back and she now revs to 8k in neutral. Before she didn't go past 5k even in neutral sputtering when at that rpm.

Went for a drive. She still doesn't go past 5k when in gear. She did once in first gear on a downhill.
Still sputters at 5k.

The clutch pushrod was replaced with a stock one that i got from germany. US postage and import tax makes everything twice as expensive :mad:

I'm running exhausts that are very close to the originals and bought UNI filters (very hard to find in Europe).

The brake master cylinder was replaced by a modern one and the brake line replaced by a steel braided one.

Everything is sorted right now.. except for the high rpms part.
Until 5k rpms the motor pulls strong and smooth at any throttle opening.
 
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