Topic: G’day! I’m an Aussie in Canada with a 1979 CB650! Cafe Resto-Mod style build.

[scunny]

Did you remove the bolt inside the sump area ?
Been years since I had mine apart, I think I can see one in your bottom pic.

[DANFROMOZ]

Hi Skunny, I had a look at that bolt but didn't think it looked like it needed to come out. I'll take that sucker out and see today, maybe that's the reason. Thanks.

[DANFROMOZ]

So I’ve pulled the extra bolt out that was in the sump area. I’ve managed to get a little bit of separation between the cases but I still haven’t been able to split them. Is there something else I should remove still? Anyone see anything on my previous pics? Does the clutch fork on the exterior of the case have to come out maybe? I’d rather not if I can avoid it....

[DANFROMOZ]

   Hi everyone, some good news! I have my frame back from the welder, he’s tacked it all in place and I’ve fitted up the tank, wheels, etc, to get an idea of the lines and angles. I’m a bit concerned with how much rear travel there is at the back, or lack of travel actually...
   Do you think it looks ok or a bit low? There’s no motor or human on the bike yet and it’s already sitting low. I’m planning on getting custom shocks from Racetech, so I’m wondering if I could just order slightly longer shocks with adjustable ride height or something? I’ll call them for their opinion, but would love to hear from people here, as I figure many of you have been down this road and would have some great opinions....? I’d like to get the frame back to the welder ASAP, to get it welded up, so the sooner the better if you have an opinion! Thanks in advance!

[Sigmund]

   Hi everyone, some good news! I have my frame back from the welder, he’s tacked it all in place and I’ve fitted up the tank, wheels, etc, to get an idea of the lines and angles. I’m a bit concerned with how much rear travel there is at the back, or lack of travel actually...
   Do you think it looks ok or a bit low? There’s no motor or human on the bike yet and it’s already sitting low. I’m planning on getting custom shocks from Racetech, so I’m wondering if I could just order slightly longer shocks with adjustable ride height or something? I’ll call them for their opinion, but would love to hear from people here, as I figure many of you have been down this road and would have some great opinions....? I’d like to get the frame back to the welder ASAP, to get it welded up, so the sooner the better if you have an opinion! Thanks in advance!

Hi Dan from OZ, Tim from OZ here...
1) You want about 100mm trail to have a mix of fast turn in (So it doesn't feel like it was designed by HD )  and stability at speed so it's not dangerous! 
2) Thinking of the CBR600 or GSXR.  If you ran a 17" front and got the same rake angle of 24 degrees on the front forks, then you would be at 95mm trail  - (That's a sport bike though and runs a damper) You however, are running an 18" front and about 25.5 degrees, so that gives more trail.  I think at the moment you would be at around 120mm trail (Very stable/a bit slow) - This is also because you have the std offset on the triple.
3) Getting it down requires a higher rear end or custom triple- win/win as you have pointed out, the rear looks quite low at the moment.
4) Do some calculations and measurements, see what you come up with, but the short answer is that yes, you can go higher with longer rear shocks.
Tim

[DANFROMOZ]

I’ve taken another look at the crankcases today. The rotor side seems pretty free but the timing plate and clutch side doesn’t. I’ve taken the timing plate right off and don’t believe you need to take the clutch off. I don’t want to get/make the socket for the clutch if I can help it, as the clutch was replaced by the PO. Do I need to remove the clutch selector fork thing? I removed the bolt in the sump area and disconnected the primary chain tensioner spring in the sump area too. Any ideas? It’s going to be similar to CB750 & CB550 to some extent I think, so I’m open to any suggestions. I have a feeling it’s something many of you have come across, I see the question asked a lot, but not a lot of answers. Thanks again.

[DANFROMOZ]

The manual says that the primary shaft needs to be removed to split the cases, but it suggests removing a bunch of items I’ve seen other guys not need to remove to get the cases apart. Can anyone tell me if this is something I do have to do? I don’t have a slide hammer to remove it so I’ll be using the engine mounting bolt instead. I’m going in....

[DANFROMOZ]

   Hi everyone, some good news! I have my frame back from the welder, he’s tacked it all in place and I’ve fitted up the tank, wheels, etc, to get an idea of the lines and angles. I’m a bit concerned with how much rear travel there is at the back, or lack of travel actually...
   Do you think it looks ok or a bit low? There’s no motor or human on the bike yet and it’s already sitting low. I’m planning on getting custom shocks from Racetech, so I’m wondering if I could just order slightly longer shocks with adjustable ride height or something? I’ll call them for their opinion, but would love to hear from people here, as I figure many of you have been down this road and would have some great opinions....? I’d like to get the frame back to the welder ASAP, to get it welded up, so the sooner the better if you have an opinion! Thanks in advance!

Hi Dan from OZ, Tim from OZ here...
1) You want about 100mm trail to have a mix of fast turn in (So it doesn't feel like it was designed by HD )  and stability at speed so it's not dangerous! 
2) Thinking of the CBR600 or GSXR.  If you ran a 17" front and got the same rake angle of 24 degrees on the front forks, then you would be at 95mm trail  - (That's a sport bike though and runs a damper) You however, are running an 18" front and about 25.5 degrees, so that gives more trail.  I think at the moment you would be at around 120mm trail (Very stable/a bit slow) - This is also because you have the std offset on the triple.
3) Getting it down requires a higher rear end or custom triple- win/win as you have pointed out, the rear looks quite low at the moment.
4) Do some calculations and measurements, see what you come up with, but the short answer is that yes, you can go higher with longer rear shocks.
Tim

Thanks Tim from Oz, appreciate you taking the time to explain all that. I spoke to Jeff from Racetech today and he also suggested it’ll be ok if I make sure I measure certain criteria when the time comes, so that’s what I’ll do.
   Now I just have to get those damn crankcase halves split.... I’ll check it again tomorrow sometime.

[DANFROMOZ]

Ok, finally got the Crankcase split. What a PITA that it was. Just the “not knowing if I’m doing it right” factor was killing me. Anyway, I ended up making the 4 pronged tool for the clutch nut removal with a 24mm socket and just cutting the notches in with a Dremel. I think a 25mm may have been a bit better but I didn’t have one laying around.
   I used the engine mounting bolt for a hammer slide as suggested in my manual and just used a 30mm (I think) socket as the weight/hammer part. It came out pretty easy, but the manuals pretty vague about what to take off/out.
    Anyway, the cases are open and I’ve taken a look at the crank bearings. I think they look alright, they are marked but I’m thinking not so bad because I don’t see the copper showing through....?
    I think I’ll get some plasti-guage strip things and check the clearances, etc, anyway.

   If anyone has an idea or opinion on the bearings in the pics, I’d love to hear it?
   

[Sigmund]

The "look" okay from here... The one with more wear probably was a tighter fit to start with. 
Having said that, mine were similar and I replaced every bearing, even the 4 transmission bearings and one is hard to find (and $$$ when you do) - This was just a "I want this to be like new and lessen the chance of re-opening".

I would suggest that crank bearings can be measured and re used if in spec. I would get big end (wrist pin) bearings if you can, as they cop most of the force. You will need 8 half bearing shells in appropriate sizes.
*Look at what's in there by the colour, and use plasti gauge to check clearance* (40 years old/may not be able to see)
*There are also letters stamped on the back of the case that tell you what the case sizes are for crank bearings*
Good luck.

[DANFROMOZ]

The "look" okay from here... The one with more wear probably was a tighter fit to start with. 
Having said that, mine were similar and I replaced every bearing, even the 4 transmission bearings and one is hard to find (and $$$ when you do) - This was just a "I want this to be like new and lessen the chance of re-opening".

I would suggest that crank bearings can be measured and re used if in spec. I would get big end (wrist pin) bearings if you can, as they cop most of the force. You will need 8 half bearing shells in appropriate sizes.
*Look at what's in there by the colour, and use plati gauge to check clearance* (40 years old/may not be able to see)
*There are also letters stamped on the back of the case that tell you what the case sizes are for crank bearings*
Good luck.

Really appreciate your help Tim, it's nice to get some confirmation of what I think is the way to go. I've got the Plasti-gauge kit on it's way and I'll see what comes of it. I'll check back in before making my decision on what bearings I'm replacing. I don't want to cut corners after all this, I'm a "no regrets" kinda fella....

[DANFROMOZ]

Ok, so I’ve checked my internals and bearing classification markings and I’m struggling to grasp how to determine what colour bearings I require. It would probably make it easier to understand if my markings were clearer, but I can only make out some and not others.... I’ve looked at other posts on here and googled and YouTubed but I’m not getting very far.
   I thought post some pics of the markings here to see if anyone can offer me a hand working them out? It’s be greatly appreciated.... I have a mechanic friend coming around tomorrow to help measure the journals, etc, with a micrometer, which might help me get to the bottom of the sizes,  it I’m still unsure what I’m cross referencing I spose.... there also doesn’t seem to be any colour on the edge of the bearing shells, which I’ve read can sometimes be there. Ive worked out the BBCCB on the crankcase but that’s about it. Any ideas guys?

[DANFROMOZ]

I’m happy with the general dimensions of the bike now it’s welded and mocked up though, so here’s some pics of that.

[DANFROMOZ]

  Ok, I’ve found more info after looking at the crankcase halves. The bearing shells still have the colours on them, so from left to right they are green, green, brown, green, brown. It’s the same colours and order on the top and bottom cases. The brown looks like it could be yellow, it’s quite light, so I’ll need to double check that.
   I’ll be measuring with the micrometer tomorrow, can I just replace them with the same colour new bearing shells? Or depending on wear etc, determine if another colour is now required....?

   I don’t think I’m getting it quite right in my head here....

[SOHC4 Cafe Racer Fan]

Stick with the same bearing shells.  The sizes are also stamped onto the outer side of the crankcase.

Mock-up looks excellent.

I forgot to ask before.  What offset did you specify on your Cognitomoto triples?

[DANFROMOZ]

Stick with the same bearing shells.  The sizes are also stamped onto the outer side of the crankcase.

Mock-up looks excellent.

I forgot to ask before.  What offset did you specify on your Cognitomoto triples?

Yesss! I'm so glad to hear from you SOHC4! I'll order a new set of the same bearing shells, but after reading some of the older posts on the bearing shells, I'm thinking I might plastigauge these ones to see how they turn out. Other guys are saying that they can last quite a while and run well when they're worn in and last for years....? Could keep the new shells as spare maybe.
   Thanks for the vote of confidence on the mock-up! Good question about the triple tree offset, I'll check my records on that and reply back here.

   Question: I've managed to find most of the markings related to the crank and conrod bearing shells, but cannot seem to track down the conrod markings that are supposed to be on the crank weight area, see pics. I have #1 on one side of conrods and what looks  to be the letter "F" on the other side of the conrods, but other then one "AF" marking on the rough crank weight section there doesn't seem to be any other markings...? Do you think that means theyre all "A"?
     Still in two minds on whether to just leave the conrods attached and just bolt it together after plastigauging just the crank, but could pull them apart, check the colour of the bearings on the conrods for sure, plastigauge them too and order a set for later also, which I'd like to have either way I think.
     Pretty sure I'll take the long complicated road here, but just wonder when I hear how bullet proof these supposedly are and how they run better when they've been run in.

[DANFROMOZ]

I had a look at my records SOHC4 & they had it as a complete custom front GSX-R setup. They supplied me with the forks and all. I remember when ordering online they had a drop down menu with the angle options I think, but I just spoke to Devin and explained what I was doing and went with his suggestion on that, so I’d suggest doing the same just to be sure. I seem to remember him saying he’d go the same as a CB750 I think, but you’d be wanting to double check that. Who even knows, until I’m riding this down the road, it may not even be a good angle until I try it. Hope that helps a bit.

[SOHC4 Cafe Racer Fan]

I had a look at my records SOHC4 & they had it as a complete custom front GSX-R setup. They supplied me with the forks and all. I remember when ordering online they had a drop down menu with the angle options I think, but I just spoke to Devin and explained what I was doing and went with his suggestion on that, so I’d suggest doing the same just to be sure. I seem to remember him saying he’d go the same as a CB750 I think, but you’d be wanting to double check that. Who even knows, until I’m riding this down the road, it may not even be a good angle until I try it. Hope that helps a bit.

If you gave Devin the specs of your bike, and an 18" wheel, he'd select the appropriate offset to restore it to the 650 offset.

[Sigmund]

I had a look at my records SOHC4 & they had it as a complete custom front GSX-R setup. They supplied me with the forks and all. I remember when ordering online they had a drop down menu with the angle options

If you gave Devin the specs of your bike, and an 18" wheel, he'd select the appropriate offset to restore it to the 650 offset.

It looks like a std GSXR 30mm offset.

[Sigmund]

How are you going with it all? Have you worked out your bearing sizes? Numbers are what you look at, not the letters. I had to use a fluro light to read the faded numbers on the crank/conrods.

[DANFROMOZ]

I had a look at my records SOHC4 & they had it as a complete custom front GSX-R setup. They supplied me with the forks and all. I remember when ordering online they had a drop down menu with the angle options

If you gave Devin the specs of your bike, and an 18" wheel, he'd select the appropriate offset to restore it to the 650 offset.

It looks like a std GSXR 30mm offset.

Hi Sigmund,
   That sounds familiar, I think they could be 30mm....

[DANFROMOZ]

How are you going with it all? Have you worked out your bearing sizes? Numbers are what you look at, not the letters. I had to use a fluro light to read the faded numbers on the crank/conrods.

  Thanks for asking Sigmund. I actually got a bunch of stuff done on the weekend. I’ll post some pics of what I got up to. My mechanic mate Landon turned up Friday night with his set of Micrometers and we measured the main journals and Con Rod journals.
   We then plastigauged all 5 sets of main bearings and also the Con Rod ones too. Turns out it looks like I’ve got plenty of meat on them still.
   We had between .0015 & .0020 clearance on the mains and between .0010 & .0015 on the Con Rod clearance. Not sure if I’m supposed to have an extra zero on those numbers but you know what I mean, I don't have the numbers right here.
   From memory I have all brown bearings for the Con Rods and Green, Green, Brown, Green and Brown, left to right for the Mains.
   

[DANFROMOZ]

So I’m going to keep everything just as it is with the bearings. I’ll probably replace some of the rubber seals, though the current ones look pretty good. I’ll clean up the cases and put it back together. I think I’ll order some new HD Head bolts, but still not sure if I should get new Rod bolts, any thoughts?

[DANFROMOZ]

Also, I noticed some pretty heavy grooves in the crankcase where the large transmission bearings lie in the case halves but the actual roller bearings on the shaft seem to be in pretty good shape... should I replace them or refinish the semi circle holes in the crankcase itself, any ideas on that anyone?
  I’ll post a pic or two to explain it more when I get a chance.

[DANFROMOZ]

So here are some pics of the wear marks I was talking about in my previous post. Anyone have any advice on whether I should just leave them as is or maybe refinish those areas with something to smooth them out a bit?