Topic: 1975 CB550K gift, Cafe build

[rollypoli]

I have loved the 70s Honda 4 cylinders and they are definitely one of my dream motorcycles. This last fall a family member told me they had a 550 in their garage that they parked cause it was overheating on cyl 1. I asked if they wanted to sell it to me and they just offered to give it to me since it needed a decent amount of work.

Starting off the bike was a kind of hacked together cafe bike. I noticed that they had definitely not been knowledgeable when it came to electronics so all the modified wires had been twisted back together and taped instead of crimping or soldering. So I fixed all the wiring around the battery and rectifiers. Thankfully the frame was repainted 5 years ago so it was close to perfect minus where the pods rubbed on the frame.

Next I did a full top end rebuild and carb rebuild, The number 1 carb bowl was filled with crap like ethanol buildup or something and it was clear it would need to be replaced. The top end rebuild went well even though I didn't have all the info I have now. I still am waiting on the endcap o-rings as those are leaking on one or both sides, and I am worried about a possible headgasket oil leak (IDK if it is why but I was given generic full synthetic oil and from people on here I think that may be the source of the head seepage and clutch slipping a bit more than it should).

After doing those fixed the bike started right up which felt amazing, but there is the new issue of tuning the stupid carbs . The previous owner had put on A 4 to 1 exhaust open about 8" after the merger pipe, and installed those cheap little blue/gray pod filters with the chrome caps. Sadly the two outer ones rub on the frame so the paint is gone where those touch and there is a little surface rust there (Nothing I cant fix). My biggest question is will I ever be able to tune this bike right? or will it forever run like crap. I wanna use it on weekends for cruises and such and be able to use most or all of my throttle range smoothly. Would nicer pods, velocity stacks, or another option work better? I don't love the look of the stock intake as it is all open right now and it looks great. I am good with CAD and have full access to a machine shop so if making something where all the carbs share one larger intake is something that would improve performance I would be happy to design one. I just don't wanna go back to stock as Id have to buy a full stock intake which would cost a lot more than me making one.

When it comes to the body stuff I put superbike bars on but I feel they sit just a bit high, Y know of an old fiberglass Yoshimura cb750 Racer tank and seat that I would like to get and do a endurance/track style bike with the tank, seat and cowl.

I absolutely love the sound of this bike, I want to put a small silencer in the exhaust and replace the pods for now, but If The pods are okay and I can tune it this way it would save some money that I don't have a lot of extra to spare rn.

I thought maybe this topic would be a good place to show my build process or ask some questions along the way. Please don't be rude I have a lot to learn but I am happy to do so.

[Scott S]

http://forums.sohc4.net/index.php/topic,182280.0.html

[rollypoli]

I have read a lot of that. It just comes down to. Can I do something else that works or will stock air box be the only way to go. They aren’t exactly cheap nowadays

[Scott S]

 The thread pretty much explains it: invest in jets, time, spark plugs, possibly dyno tuning.....or....put it back to stock.
 There is no magic combination that works for everyone in every combination at every location.  Except for the stock set up.

[calj737]

That extra short exhaust will cause you some persistent tuning problems. Even though there are lots of 4:1 systems out there running stock or pod filter, the added length aids in creating the desired backpressure.

Yes, you can run pods. There are much better quality units out there, they run about $150 from K&N. You can get a “bread basket” type filter too. Then there is the “Uni Filter” mod by a member.

Your motorcycle needs to run motorcylce-specific oil that is suited for a “wet clutch”. Synthetic is perfectly fine, but it needs to be for a wet clutch. Standard automotive oil does not have the friction modifiers added and it WILL cause clutch slippage.

Before you tear down the top end to address a possible head gasket leak, take the time to re-torque the head properly by the book. Sequence matters, and use a proper torque wrench. And proper oil. It won’t fix your end cap leaks, but it can resolve other possible problems.

[dave500]

put the stock airbox back on it full stop,itll be more ridable all over.

[Shtonecb500]

Im not knocking pods or alternative options, but my experience has been best with stock air box set ups, a honda that runs like #$%* is probably one of the most disappointing things you can try to ride.

[rollypoli]

put the stock airbox back on it full stop,itll be more ridable all over.

See the issue is I don’t have the stock one. So I’d have to spend $175 just to get the box

[rollypoli]

That extra short exhaust will cause you some persistent tuning problems. Even though there are lots of 4:1 systems out there running stock or pod filter, the added length aids in creating the desired backpressure.

Yes, you can run pods. There are much better quality units out there, they run about $150 from K&N. You can get a “bread basket” type filter too. Then there is the “Uni Filter” mod by a member.

Your motorcycle needs to run motorcylce-specific oil that is suited for a “wet clutch”. Synthetic is perfectly fine, but it needs to be for a wet clutch. Standard automotive oil does not have the friction modifiers added and it WILL cause clutch slippage.

Before you tear down the top end to address a possible head gasket leak, take the time to re-torque the head properly by the book. Sequence matters, and use a proper torque wrench. And proper oil. It won’t fix your end cap leaks, but it can resolve other possible problems.

Thank you. I was thinking of adding a silencer to the exhaust would that help with the back pressure as much as lengthening the exhaust? 
Also I’m glad to hear you repeat thinks I was already thinking makes me feel a bit more solid in my plans. Is rotella T4 what I’ve been seeing recommended. Or is there something better to go with?

And I’ll give the head torque a shot when the orings come in for the caps

[BrickWoll]

A "midway" option between the pods and stock is a breadbox filter.  Still going to run you at least $175.  It has been my experience that the bike runs MUCH better all around since I switched ('77 550 K3). 

If you haven't already explored this option, I got mine from Steel Dragon:  http://www.steeldragonperformance.com/air_boxes_7.html

[newday777]

That extra short exhaust will cause you some persistent tuning problems. Even though there are lots of 4:1 systems out there running stock or pod filter, the added length aids in creating the desired backpressure.

Yes, you can run pods. There are much better quality units out there, they run about $150 from K&N. You can get a “bread basket” type filter too. Then there is the “Uni Filter” mod by a member.

Your motorcycle needs to run motorcylce-specific oil that is suited for a “wet clutch”. Synthetic is perfectly fine, but it needs to be for a wet clutch. Standard automotive oil does not have the friction modifiers added and it WILL cause clutch slippage.

Before you tear down the top end to address a possible head gasket leak, take the time to re-torque the head properly by the book. Sequence matters, and use a proper torque wrench. And proper oil. It won’t fix your end cap leaks, but it can resolve other possible problems.

Thank you. I was thinking of adding a silencer to the exhaust would that help with the back pressure as much as lengthening the exhaust? 
Also I’m glad to hear you repeat thinks I was already thinking makes me feel a bit more solid in my plans. Is rotella T4 what I’ve been seeing recommended. Or is there something better to go with?

And I’ll give the head torque a shot when the orings come in for the caps

Your header is missing the muffler.. It looks like you have the Delkavic 4into1 header(springs to hold to the transition collector) The muffler will help in tuning.
Try contacting 4into1.com to see if they have a muffler available that isn't listed on their site.

https://4into1.com/delkevic-4into1-stainless-steel-headers-honda-cb500-cb550/

[calj737]

Thank you. I was thinking of adding a silencer to the exhaust would that help with the back pressure as much as lengthening the exhaust?

Cone engineering makes a variety of mufflers suitable for installation on your bike.

Is rotella T4 what I’ve been seeing recommended. Or is there something better to go with?

A perfectly suitable choice.

[rollypoli]

Thank you. I was thinking of adding a silencer to the exhaust would that help with the back pressure as much as lengthening the exhaust?

Cone engineering makes a variety of mufflers suitable for installation on your bike.

I was thinking of putting a fiberglass wrapped drilled pipe in the end of the existing exit. Would buying a cone be better? I just don’t love the look of them

[rollypoli]

A "midway" option between the pods and stock is a breadbox filter.  Still going to run you at least $175.  It has been my experience that the bike runs MUCH better all around since I switched ('77 550 K3). 

If you haven't already explored this option, I got mine from Steel Dragon:  http://www.steeldragonperformance.com/air_boxes_7.html

Sweet. I was trying to see if the breadbox style was better but I haven’t really seen info on them. I can make one myself with either the waterjet or cnc I have. So I save a bit of money. I like the look of the cognito one. Might make one similar to that.

[Gurp]

Maybe post in the wanted section. People part out bikes often enough. May even find a old antipod or something cool around.
(You'll have to search "antipod"

[Bankerdanny]

While am in the stock airbox camp, I will say that my 550F came with those same cheap pods and a Kerker in place of the stock 4-1. I rode it thousands of miles with the pods from Chicago to high in the Colorado mountains without any serious mixture related issues (although TwoTired rode it and said it was down on power compared to his bikes).

I did put a stock airbox on when I finally got one for a good price, but your bike can run perfectly fine if not perfect as it is now. The pods were actually a blessing when I was dealing with sticky floats 1/2 way through my trip. The carbs came off in 10 minutes and went back in just as easily at my camp spot with the tools I brought with me. With a stock airbox carbs off and back on can easily be an hour job on a 500/550. 750 only guys don't know how easy they have it.

[rollypoli]

Some fun updates. Bike ran great. Did probably 300 miles so far. But out of no where there was a bunch of chain noise and then. Nothing. Engine locked up. It was the cam chain sprocket. And it took the head with it. So now I’m looking for a new cb550 head and valve cover. But while I search. I started tearing her down to get all the metal and crap out. I have it all down now.
I feel like the crank shaft bearings and I assume the rod bearing could use replacing. I’m a little scared about this as I haven’t gone this deep in a motor before. How hard are the bearings to get?
Second the ball bearings in the case like for the main shaft and the trans. Should I replace them? They are original. And I have no idea how I’m gonna find those ones. But yeah. Any tips and tricks would be nice.

[rollypoli]

Also since I’m doing a full rebuild. I am thinking I’ll buy some high compression pistons. I think I should get them matched to the cylinders. And get all the cylinders bored to the pistons specs. So should I get .25 or .5 oversized pistons? 
Also recommendations on high compression pistons would be greatly appreciated the only ones I’ve seen so far are wiseco 10:1.

[calj737]

I’m a big fan of the Wiseco pistons. Boring and honing will be required with new pistons. As for the head/cam, if you are opting for Wisecos, then grab a MegaCycle 126-00 cam and ship the head and intakes to Mike Rieck for porting, new valve seats, and milling. You’ll invest some money, but your bike will run like a stabbed rat afterward.

[rollypoli]

I’m a big fan of the Wiseco pistons. Boring and honing will be required with new pistons. As for the head/cam, if you are opting for Wisecos, then grab a MegaCycle 126-00 cam and ship the head and intakes to Mike Rieck for porting, new valve seats, and milling. You’ll invest some money, but your bike will run like a stabbed rat afterward.

Already talking to Mike. He mentioned the je pistons because they work with the oversized intake valves so I may go that route.

[flatlander]

this thread should be in the project shop, no?

i got my 550 head done by mike, also with oversize intake valves, porting, milling, all his good stuff... he recommended i use the wiseco pistons with it, apparently they're more precisely manufactured. my setup works great, the bike pulls like a train. but yes, je has them in larger bore sizes and higher compression. would be interesting to know what his current thinking is on them vs the wisecos.

re. your exhaust:
i have a relatively long 4-4. initially with straight-through dampers at the ends. that worked well, certainly at high rpms. more recently, i added some additional dampers further down the mufflers. the effect is noticeably more torque, and there's no significant penalty at the top.
that's just to illustrate what cal said: that this engine does like a bit of back pressure.

re. air intake:
i use the original plenum, with a single k&n filter attached. the pod flows a lot better than the OEM filter yet the intake behaviour is not changed from stock, with the velocity stacks that are integrated in that setup. i know you're not a friend of the stock intake's look, just throwing this out there.

[bryanj]

Shell bearings in some sizes are getting very difficult to find and are very expensive so unless badly worn or marked leave well alone BUT they must go back in the same place they come out of.
Primary chains and damper rubbers wear quickly, most gearbox bearings are very overspecked and last a long time, some are not easy to get

[calj737]

I’m a big fan of the Wiseco pistons. Boring and honing will be required with new pistons. As for the head/cam, if you are opting for Wisecos, then grab a MegaCycle 126-00 cam and ship the head and intakes to Mike Rieck for porting, new valve seats, and milling. You’ll invest some money, but your bike will run like a stabbed rat afterward.

Already talking to Mike. He mentioned the je pistons because they work with the oversized intake valves so I may go that route.

Both brands of pistons work with oversized valves, but depending upon the cam you choose, the Wisecos would need to be pocketed where the JEs may not. I have some Wisecos in my 550 but have the 126-20 cam and had to mill the dome.

[flatlander]

Both brands of pistons work with oversized valves, but depending upon the cam you choose, the Wisecos would need to be pocketed where the JEs may not. I have some Wisecos in my 550 but have the 126-20 cam and had to mill the dome.

the wiseco work out of the box with 126-00 and 358a cams. i've used both. but you do need to measure clearances with any new combination.

[rollypoli]

this thread should be in the project shop, no?

i got my 550 head done by mike, also with oversize intake valves, porting, milling, all his good stuff... he recommended i use the wiseco pistons with it, apparently they're more precisely manufactured. my setup works great, the bike pulls like a train. but yes, je has them in larger bore sizes and higher compression. would be interesting to know what his current thinking is on them vs the wisecos.

re. your exhaust:
i have a relatively long 4-4. initially with straight-through dampers at the ends. that worked well, certainly at high rpms. more recently, i added some additional dampers further down the mufflers. the effect is noticeably more torque, and there's no significant penalty at the top.
that's just to illustrate what cal said: that this engine does like a bit of back pressure.

re. air intake:
i use the original plenum, with a single k&n filter attached. the pod flows a lot better than the OEM filter yet the intake behaviour is not changed from stock, with the velocity stacks that are integrated in that setup. i know you're not a friend of the stock intake's look, just throwing this out there.

Thanks for the info.  I believe the wiseco 10:1 only would work with stock valves.
With the intake. I would do something like your setup if I had the stock box. But I don’t and people seem to want a lot for them. So I just decided to stick with these. Or design a breadbox style filter.

[rollypoli]

Shell bearings in some sizes are getting very difficult to find and are very expensive so unless badly worn or marked leave well alone BUT they must go back in the same place they come out of.
Primary chains and damper rubbers wear quickly, most gearbox bearings are very overspecked and last a long time, some are not easy to get

Sounds good. I’ll leave them be then.

[calj737]

this thread should be in the project shop, no?

i got my 550 head done by mike, also with oversize intake valves, porting, milling, all his good stuff... he recommended i use the wiseco pistons with it, apparently they're more precisely manufactured.

Thanks for the info.  I believe the wiseco 10:1 only would work with stock valves.
With the intake. I would do something like your setup if I had the stock box. But I don’t and people seem to want a lot for them. So I just decided to stick with these. Or design a breadbox style filter.

Not correct. Flatlander uses +1mm oversized intakes with a 126-00 cam with no interference issues. I don’t know his squish dimension, mine is 0.032 and a much more aggressive cam, hence the pockets milled. Either way, JE or Wiseco are both very good pistons.

[rollypoli]

this thread should be in the project shop, no?

i got my 550 head done by mike, also with oversize intake valves, porting, milling, all his good stuff... he recommended i use the wiseco pistons with it, apparently they're more precisely manufactured.

Thanks for the info.  I believe the wiseco 10:1 only would work with stock valves.
With the intake. I would do something like your setup if I had the stock box. But I don’t and people seem to want a lot for them. So I just decided to stick with these. Or design a breadbox style filter.

Not correct. Flatlander uses +1mm oversized intakes with a 126-00 cam with no interference issues. I don’t know his squish dimension, mine is 0.032 and a much more aggressive cam, hence the pockets milled. Either way, JE or Wiseco are both very good pistons.

No interference on wiseco 10:1 59mm pistons? I’m just going off what I have been told.

[calj737]

It’s all about the cam specs…

[flatlander]

Not correct. Flatlander uses +1mm oversized intakes with a 126-00 cam with no interference issues. I don’t know his squish dimension, mine is 0.032 and a much more aggressive cam, hence the pockets milled. Either way, JE or Wiseco are both very good pistons.

No interference on wiseco 10:1 59mm pistons? I’m just going off what I have been told.

right, i use the wiseco 59mm pistons with +1mm intake valves. this works with the 126-00 and 358a cams, without having to modify the pistons. i have about .040 squish, so more space than cal with a lower lift cam (dammit should i take it lower???).
if mike knows the piston/cam/valve size combo he'll be able to make sure that your squish works out as well.

[rollypoli]

Thanks for all of the information on the wiseco pistons and intake advice so far

Back to the update I was gonna put in that old thread
Well. I haven’t updated this thread is a long time.
After tearing the bike down. I needed a new head and chain and sprocket. Not too bad. The crank and rod bearings seemed in spec still but they were definitely well worn. Once the whole thing was in pieces I realized that the previous owner not only didn’t touch the engine he did not replace a single item on the bike. Stock wheel spokes, stock bearings, stock seals, bushings, stock drum brake, the only thing done was a tapered steering bearing which is nice.
 Anyway. After all that and getting studs, Cush drive rubber, primary chain, all new crank and rod bearings, and oil seals. I decided that I don’t have time and don’t want to spend more on doing the power upgrades this winter. I want to ride the bike especially now that it will be in much better condition. So the head will wait till fall to send to Mike. This also gives me time to find someone in Minnesota/Wisconsin to do the boring and such for the Wisecos.

Here’s some photos of things I’m currently working on.
1. Got the oem wheel bearings out and replaced
2. Case is starting to go back together. Just have to plastigauge the crank journal bearings.
3. All covers were blasted and hit with some engine clear to keep that look. The block,jugs and head will be black.
4. Dual disc conversion is going great. Got a second disc and caliper for $35. Then I found someone parting out their cb650 with a cbr600r brake master cylinder with braided lines. Got that for $50. Should be a great upgrade when it’s all put together.
5. Not shown yet but I stripped the paint on the swingarm and have bushings coming to replace the stock ones. The pivot axle seems a bit too loose to me. And I am 50% of the way done with my wiring harness. Stitching to all Deutsch DT/DTM connectors. I’m an electrical engineering student so I’ve been working on a board built into the stock tech housing that does speed, switching, replaces the ssm. And some other fun things.