Topic: The "Tombstone" shed find and its older sister "Redstone".

[Terry in Australia]

Sweet! I've never really been a fan of the smaller SOHC4's, I restored a 350F in 1996 and loved it, but it was pretty slow, even though it sounded like it was doing the ton at 30 MPH, but I must admit I always thought the early 500's looked cool, especially with the OEM pipes.

I didn't realise you were from Holland mate, I spent some very enjoyable weeks in Amsterdam in 1974 smoking weed with American draft dodgers and eating cheeseburgers from vending machines, washed down with Heineken or Lowenbrau beer. I wish I had a time machine so I could go back and do it again. Subscribed.

And Sean, I've got at least one pair of those handlebars here, maybe more, they were very popular here in Oz back in the day, if you could bear paying the shipping from Oz, you can have them as a Christmas present.    

[seanbarney41]

Sweet! I've never really been a fan of the smaller SOHC4's, I restored a 350F in 1996 and loved it, but it was pretty slow, even though it sounded like it was doing the ton at 30 MPH, but I must admit I always thought the early 500's looked cool, especially with the OEM pipes.

I didn't realise you were from Holland mate, I spent some very enjoyable weeks in Amsterdam in 1974 smoking weed with American draft dodgers and eating cheeseburgers from vending machines, washed down with Heineken or Lowenbrau beer. I wish I had a time machine so I could go back and do it again. Subscribed.

And Sean, I've got at least one pair of those handlebars here, maybe more, they were very popular here in Oz back in the day, if you could bear paying the shipping from Oz, you can have them as a Christmas present.

wow, thanks Terry!  pming...

[web]

Terry, the thing you need is a flying machine, not a time machine 
The selection of beers is so much better these days. Although if you have fond memories of Heineken and cheap cheeseburgers, who am I to argue with that 

Meanwhile holidays and other priorities took over, but I did spend a bit of time on the old Fours again.

Earlier, I had put some effort into getting the brake line off in one piece, only to have to put it back in to get the piston out 
Usually compressed air does the trick, but this time my trusty bicycle pump gave up before the piston showed any sign of moment. Figures...

But after re-connecting and re-bleeding, it popped right out into the old frying pan.


Note that this is AFTER the first shop towel wipedown. I thought gray matter belonged in your head, but it looks like a PO collected it in his bikes' brakes. I guess he didn't need it anymore.

Anyway, the piston cleaned up to a shine, so it should be all good with just a new seal.



On to engine business. I took the redstone for its first ride in my posession. Well, a very short ride. It started up OK cold, though I did have to hold the throttle open a little bit (say to 1500rpm or so).
But about a mile down the road it refused to idle, where the definition of idle is to be taken quite broadly: anything under half throttle or 5000 rpm and it would just die, with no hope of ever starting again. So I took it up the sidewalk and after a few minutes of trying to look like I knew what I was doing, it started up again, with some effort. So I rode straight home, and on the last intersection... yup, I had to slow down for other traffic and poof, dead again. Had to walk it the rest of the way home. Have to say, btw, I like it. Handles differently than a modern bike, but certainly no worse.

Btw does anyone recognise that 4-1 exhaust? Whatever it is, it is WAY WAY WAY too loud for me. Also, I like to change oil without having to drop the pipes first.

So then Deltarider came over and some tire-kicking was done. We also drained the tombstone (that had been sitting for 20 something years) carb bowls and a dark oily substance came out. I'm unsure whether that's just 20 year old fuel or whether someone put in some conservation fluid. Either way, I'm afraid I'll have to take the carbs apart before even trying to start it up. I did 'fix' its electrical issues: it helps if you plug the ignition switch in fully. So at least it's had some oil pressure now from cranking it over.

For the redstone "idle" issues, we checked #4 carb float level, and I borrowed his drain screw adapter to do the others later. Then we took a look under the points covers and saw whoever adjusted the points, may have confused plug gap with points gap    Thus dwell angle was little more than half of what it should've been. Strangely it wanted to rev quite happily - just didn't want to "idle" warm (well, didn't want ANYTHING below 5k rpm or half throttle)

Anyway, after Deltarider left, I adjusted both bikes' points and static timing. To get 'em in the ballpark, you know.
Contrary to expectation the "sitting for 20 years" Tombstone was totally fine, needed very little adjustment. The "rode it yesterday" Redstone however, was an entirely different story. Even with the points gap set correctly, ignition was still way, way, WAY off. Closer to the 2-3 marks than the 1-4 marks. So just before I took out a spark plug to check the (markings on the) advance plate for misalignment, Deltarider suggested I take a look at the points cam. With that tiny little centerpoint dot on it... that is apparently supposed to point towards the TEC logo. Sure enough, the points cam was installed 180 degrees off. OK - so I reversed it, put it all back together aaand... still way off. Ok. Points gap again. Way wide again. With that re-adjusted though, everything came together nicely as on the Tombstone. Having two of these bikes really helps!

But how did it even run with the points cam 180 degress off? Easy - the coil wires were also reversed 
So ... good progress was made tidying it up a bit. Whether that's enough to make it actually rideable for more than a mile remains to be seen. By the time I had it buttoned back up, it was too late to start it up with this OBNOXIOUS pipe.

[Terry in Australia]

Wow, that was a read and a half! I'm surprised that Deltarider didn't get your bikes running sweetly, I thought he was an expert on CB500's, and he believes that the lesser 4's were the best bikes ever made, in his humble(?) Opinion?

The no idle thing sounds like blocked pilot jets to me, but I'm sure you've already gone through the complete strip and clean process? That pipe looks like a Mac, both cheap and nasty, I've just put new Delkevics on both my CB750K2 and Kawasaki Z1000 special, and think that they're exceptionally good value for money, just don't buy the one with the stupid 2 stage megaphone, if you have any love of mechanical aesthetics.

Good luck with your progress, and I'm impressed with your opinion that your 40+ year old bike handles no worse than a modern bike, motorcycle engineers world wide must be gutted by that revelation!

[web]

Ah well, overdue update, so yes long read. Oops.

Deltarider didn't fix it because I didn't give him enough time  Also I wouldn't want to miss the fun myself. Rest assured he did bring his dwell meter, parts book and some other tools where I hardly knew what they were

In terms of handling I would say a modern bike can probably be put through hard cornering quicker. But really, this old bike was surprisingly stable, confidence inspiring and comfy. The often complained about brakes even felt alright for the sub 100km/h speeds I made. I would say the better cornering abilities of modern bikes also make them a little more nervous to ride, a trait I don't necessarily like. More tailored to modern tastes. And I just happen to have '70s tastes 

I didn't tear into the carbs yet. Bought the red one as a runner, so didn't want to fix anything that wasn't broken. But it looks like both bikes may need a carb job.

[Terry in Australia]

Yep, cleaning carbs doesn't fall into "unnecesary exploration", it should be seen as mandatory maintenance after so many years in a frozen barn with the dregs of fuel produced when a guilder could still buy you a beer.

Modern bikes are a revelation to ride after spending most of my time on old bikes, my son's new Royal Enfield Continental GT650 looks like a bike from our era, doesn't have much grunt, but handles and stops beautifully. I'm hoping my Kawasaki Z1000 with modern shocks, stiffer front springs, and Brembo brakes will have a similar feel, with just a much bigger kick in t he pants.

[web]

Are you seriously telling me to finally clear my workbench now? 

I get it, I guess it's unavoidable to at least see the evil lurking within.

Did read something about the 500/550 series being a better balanced bike than the 750 or many other heavier bikes of that era. Must have been written by a 500-550 owner though 
Anyway, it just works for me now, and that's what I need.

Aside from maybe the pair of these Sitos that just came up for sale locally.


Either that or have a try-and-see whether the SOHC Nighthawk 4-in-4 pipes have any chance of fitting the CB500 ?

[Terry in Australia]

Yeah, when I was young the smaller 4's were very popular with girls and very short men, who I think justified their stature with wild tales of better power to weight ratio's, superb handling and braking, blah blah blah, but in reality, they were just pissed off that they couldn't reach the ground when sitting on a big bike.

Thats ok, I quite liked the 500F, and have fond memories of a local girl who would kindly let me ride hers, with her on the back in the days before I bought my shiny new CB750. I'm not familiar with Sito's, I presume they're a European brand? I wish Delkevic would make a 4 into 2 like my old Hanco, and I'd buy one for my K1 project.

[web]

Sito is Italian.

Having had complaints about walls of text... I now present a wall of pictures!

Because dinner tables are for showing off your new pipes:



Check out the up-bend... more pronounced than I expected. Should be pretty.

They came with a set of ... mediocre bends.


So... about 10 minutes later the obnoxious 4-in-1 hit the garage floor. The nuts came off fine and left the studs in the head. Nice.



Not sure the ports are THAT much pointed in all sorts of directions though.



I guess they're not - I thought I might anneal and reuse these copper gaskets but nope... not these smashed wedges. Aside from these wedges (only one set though), a few bricks worth of carbon buildup were also pulled from the exhaust ports.

One little concern though... it looks like these have 'pea shooter' type noise killers fitted.



That's... a 2cm tube.
Outer diameter.
That's less than one inch.
Less than half the flow area of a single exhaust port.

I am not one to see restrictions everywhere where they are not, but even with the mufflers each acting as 2-cylinder plenums and cooling the gases down... that has STILL got to be a bit small, right?

Those pop rivets seem to scream DRILL ME OUT, DRILL ME OUT... maybe everyone did that in those days and they were kind of designed for that?
I don't want half rivets rattling around in some unreachable part of the baffle though, so I guess I'll just try them out as-is for now.

Oh and that little hole in the bottom has to be a drain hole right?
... then I have news, the muffler is lying on its side Italians...

[jakec]

the single muffler outlet is maybe 150% that size

[Terry in Australia]

Yep, drill those rivets and pull that mess out mate, you can always buy accessory baffles to replace them with on ebay.

[web]

Sounds like a plan. I'll still install them as-is for now, knowing they'll have to come off later anyway. I could do the ebay baffle thing then.
But for now I just want to ride the damn thing without turning heads three streets away.

The little end tube is 17mm ID which is 1/3rd the flow area of one exhaust port. Of course an exhaust valve is only (partially) open about 1/3rd of the time, so it wouldn't be so bad if they were 4-in-4's, but obviously they're not.

From poking around in there, the end tube is about 15cm long and blocked off at the end, fed by side perforations.
From the other end too, I can't reach the full length. I.e. it's definitely a chamber style muffler.

I see wads of fiberglass in its future, but for now it'll have to do.

[rb550four]

   Web, just wanted to say that I'm enjoying this thread. 3 decent projects acquired in almost as many days all in what seems to be in decent ,complete and easily rebuildable condition...an excellent place to start. 
  I like that Redstone has been making progress for you, I always liked a 500.... and a 550, and a 650 the most and this thread has them all! How much better can it get!
  I was happy for you that you found a runner, few and far between they are.
 I see that you got into the floatbowl on#4 carb and have been catching up with a spark timing issue and idling issue, and I may have missed it , but have you cleaned and sync'd those carbs yet? I only ask because if the PO did them there is no telling how long ago, are they still clean, did he do a good job,were they ever  sync'd . All of these things can contribute to idle /poor running issues. And yes it is much easier to get at all the electrical components first and equally important to properly time the spark. But all that means is that it will fire at the proper time, it'll pop on any amount of fuel given to a cylinder as long as it isn't enough to flood it, that and some air.  I believe that once you clean the carbs, fuel lines, and blow them out properly , and the petcock can't forget that, that you will find a marked difference in how it runs and after a sync ,the the pistons ,fuel and air mixture will find harmony making the your world a better place.
 Intake air passages must be clear ( left over nests and stuff like that if keeping it stock), fresh air filter never hurts , and it's important that the seal between the carbs and the manifold are good AND the Orings between the manifolds and the head is good. or harmony may elude you.
  I like the Italian pipes idea, wonder how much backpressure they produce? I concur with all who think drilling out the rivets may be a good idea but that's something you could do when tuning so you may see the actual difference at the same time. Who knows , you may end up putting the unit back together with new rivets. It'll be interesting to see what happens.

[web]

Thanks! Well I still see the 650 as a parts bike, not as a project, but who knows.

I did indeed not yet tear into any of the carbs, and I know I'll have to. I'm just getting the simpler things sorted first.
Oh, and I've been dreading to clear my workbench to make room for that job 

This weekend was mostly spent on family business, some house- and paperwork. But I also made a few tool holders for the french cleat wall, which helped clear the workbench a bit.

Then I took a few minutes to test-fit the pipes. What can I say, the fit is very nice.



The outer header pipe does need some trimming.



And that's where I got stuck, because by the time I figured that out, it was too late to wake up the neighbors with the angle grinder 

Really looking forward now, to doing an oil change WITHOUT having to remove the pipes, and to starting it up without setting off all car alarms in a 200m radius...  for now I'll just accept that it's probably restrictive as f**k.

[rb550four]

It looks like the muffler mount has been custom bent. Would the brake side fit correctly and get caught up in the foot brake if the bends were to be relieved a little bit? Ilike those pipesit cleans up the lower area and won't look vacant on the shifter side like the 4into1 headers make it look....no pipe ,just the center stand hanging there all by itself. I like your choice.
  The 650 is a parts bike? Oh my, wouldn't that 650 engine look right at home in Tombstone someday. Not to mention the air assist front forks and the dual front brakes....what fun! if you get a chance to swap the 500 shocks with the 650 shocks just for a ride comparison, I'd be interested to get your view about the ride, better or not.

[web]

Well that's the idea - mid term plan is to put the 500 engine+tranny from the Tombstone into the Redstone to return it to fully stock 500 trim. It also needs a seat cover, and then with the new pipes it'll be a nice near-original CB500.

Then the 500/550 trans from the Redstone will be converted into a 650/550 hybrid using the top half of the Nighthawk engine, to be dropped into the Tombstone. I may keep its current 4-in-1 exhaust if it cleans up well, I kinda like it. Or see if I can make the 4-in-4 Nighthawk pipes fit.

But first I want to get the redstone running as-is. Mostly to get a better feel for how these bikes work before tearing them to pieces and ending up with too many variables if it ends up not working later. That's how too many stranded projects begin.

So I'll raise the difficulty step by step.
1) Get the redstone running as-is. Bonus points if I manage to breathe some life into the tombstone as well.
2) Drop the tombstone motor into the redstone, make it run and ride well again.
3) Tear open the old redstone 500/550 motor and the 650 SOHC from the nighthawk, mix & match as documented elsewhere on this forum. Yeah, I know I can also drop in the whole 650 motor but I'd like to keep the kickstarter.

[rb550four]

 Yeah , it's allot more work to put the 650 on the 550 tranny  but, when you love a kickstarter you have to have a kickstarter, especially when you have the parts.
  A while back there was a thread about kickstart vs push button start, I seem to remember a large fan base for the kickstart. I know I'm  fan. I'm glad that they came with a push button too though I wish they didn't delete the kick  . My 500/550s have both in working condition even though I hardly ever use the button.  Have a classic be the classic. There's just something about it, a positive connection between man and machine when human energy causes the machine to come alive...unless you left the kill switch in the off position, then it doesn't feel so glorious.

[web]

Hahaha. Is this the right time to confess that I once ran my lungs out trying to push start the CB twin, cursing it for not having a kicker, only to realize that some joker had flipped the kill switch while parked...

Anyway i love and hate these kickstarters. Love because... Well you know. But hate the fact that they're always worn and wobbly, that they feel like they could strip at any time. Almost makes me want to abandon the idea and drop in the whole 650.

[web]

Hmmm... so what is that extra mount for anyway? The one on the left muffler...opposite the main mounting ear.

Since we are now asked to work from home if possible, I decided to interpret that loosely and work on the bike a bit.
Finally finished the exhaust install after trimming 3 out of 4 header pipes a bit more to make it all fit together neatly.



Better pics when I roll it out tomorrow.

[Robbo]

Hmmm... so what is that extra mount for anyway? The one on the left muffler...opposite the main mounting ear.

Since we are now asked to work from home if possible, I decided to interpret that loosely and work on the bike a bit.
Finally finished the exhaust install after trimming 3 out of 4 header pipes a bit more to make it all fit together neatly.



Better pics when I roll it out tomorrow.

The extra mount is most likely for a rubber bumper to stop the side stand from hitting the muffler.

Here’s an example of one on my CB350 twin...





Sent from my iPhone using Tapatalk

[web]

Aaah thanks!!
I did find this out the first time I took it off the sidestand 

I don't have the rubber bumper so I ended up using a zip tied wood scrap to protect the muffler for now.

Update overdue, coming up soon. Had some other fish to fry first, in our half-assed lockdown.