CB360 Cafe Project

Re: CB360 Cafe Project *Engine Time*

crazypj, I'm trying to decide if I want to use this old tensioner or not. Since I haven't actually seen a broken tensioner, I'm trying to understand it more. When the old ones break, exactly where and how does it break? Does it break straight through near one of the ends/curls? Or does the slipper material come off of the metal base?

Also, does making sure your cam chain is tensioned properly on a regular basis prevent or prolong the breaking point of the old tensioner?

I can't stand to ride a bike that I know something could go wrong at any minute, especially something that I could prevent. Is calling the tensioner a ticking time bomb and ignorant exageration?

Thanks.
 
Re: CB360 Cafe Project *Engine Time*

I got hot tip last night on a updated tensioner guide (thanks frogman). It was used, but it looked slightly better than mine. So, I'll take my chances with that one and send the old version back.

I'm still curious on the faults of the tensioner's, if anyone has any insight.
 
Re: CB360 Cafe Project *Engine Time*

From what I have gathered through reading a lot is that they break when piss poor mechanics don't tighten the cam chain during the regular maintenance schedule. So with time the chain gets loose and starts to slap the tensioner and it will eventually break it. It can also slap everything in radial arc around it so the tensionser mount, the slipper, the chain gallery, etc.

It's not hard to do either, can be done right when you change the oil, when you pull the clutch cover to clean the filter, then grab the right wrenches, make sure the engine is in the right spot loosen the adjuster, tighten and get back to buttoning up the clutch cover. Hell, make mark somewhere in the engine on that side that will show where the piston cycles are and you won't have to pull the alternator cover to check.
 
Re: CB360 Cafe Project *Engine Time*

Good idea. I might do that. I can't remember from reading my service manual, but I assume you want the #1 piston (left side from riders position?) just past TDC so that all the rockers are free? That should give the cam chain the max amount of slack for the tensioner to take out?
 
Re: CB360 Cafe Project *Engine Time*

You set at the spot where both sets of rockers are "loose", manual states 90 degrees past TDC on the left side on its compression stroke. God I love having a digital version of that thing. ;D
 
Re: CB360 Cafe Project *Engine Time*

Aside from the used tensioner guide that should be here tomorrow, I'm ready to build the engine back up. The only problem is, I have to get married tonight and the inlaws are staying the weekend. Don't you hate it when life gets in the way of your projects! I feel legitimately upset. Oh well.


Stopped by the machine shop yesterday and picked up my stuff. The head and covers were just glass blasted. I picked up some Dupli-Color Aluminum and Clear high temp paint to paint everything from the top of the jugs up. I also picked up some Dupli-Color Seme-Gloss Black for the jugs themselves.




Looks so nice, you can see that crosshatch from here.....


HPIM2304.jpg





Those are the pistons that came out of the bike, w/ fresh rings, gasket kit and 92L EK chain. Thanks to Les Barker @ The Vintage Advantage for cutting a cam chain down for me.


God I love fresh parts...


HPIM2305.jpg
 
Re: CB360 Cafe Project *Engine Time*

kMoto said:
crazypj, I'm trying to decide if I want to use this old tensioner or not. Since I haven't actually seen a broken tensioner, I'm trying to understand it more. When the old ones break, exactly where and how does it break? Does it break straight through near one of the ends/curls? Or does the slipper material come off of the metal base?

Also, does making sure your cam chain is tensioned properly on a regular basis prevent or prolong the breaking point of the old tensioner?

I can't stand to ride a bike that I know something could go wrong at any minute, especially something that I could prevent. Is calling the tensioner a ticking time bomb and ignorant exageration?

Thanks.
Click to expand...

Personally I've never had a problem with tensioner or guide, even after several thousand miles hard use (had other problems but I expected stuff to break at 10,000 rpm+)
Tensioner breaks just above 'rubber' section, seen a couple of broken ones, have a pic but can't find it
If it's serviced before chain starts rattling it doesn't seem to be an issue
 
Re: CB360 Cafe Project *Engine Time*

I finally got rid of the family yesterday and got to work on assembling my engine. Didn't make it very far tho. I was installing my counter shaft in the tranny, when I realized I was missing a the 20mm thrust washer (#2 on the schematic) behind the needle bearing on the end. How I misplaced the washer, I have no idea.


TransSchematic62.jpg



When I took everything out of the engine and placed every component directly into a zip-loc bag. I searched EVERYWHERE, three times! I looked so good that I wonder if it was even there in the first place (probably was). Not real happy with myself.

To make the situation even better, I couldn't find it for sale from any of the OEM parts suppliers. Or from any hardware/bearing supplier. I might have found one on ebay that came out of a 70's-80's CR125. It's a little thicker than the one that goes in there, but I think there will be enough room.


If anyone has a box of old tranny parts laying around (for any bike), I wouldn't mind some help.


Thrust washer dims are 20mm I.D. x Apprx. 27mm O.D. x 0.60mm Thk.
 
Re: CB360 Cafe Project *Engine Time*

Go onto mcmaster.com. Type in "shim and shim stock" in the search bar. Click "Round Shims">>"Standard">>"20mm ID". You'll probably need 2 of the .3mm thick washers to get exactly .6mm thick. The only problem I see is that they only come with an OD of 28mm. I don't know if that matters. They only come in packs of 25, but when you need a spacer, you need a spacer... It looks like #2 is used twice in your diagram, I take it you already have one?
 
Re: CB360 Cafe Project *Engine Time*

Eric P, I can't believe that I passed over those @ McMaster Carr. That was one of the first places I looked. Those would have been perfect. And yeah, there was one already in there. Actually the washer that was missing was the one in between the gears (#3 & #4), not the one behind the needle bearing. I still think that it might not have been in there to begin with.

Well, I got the tranny put back together anyway last night using the CR125 shim I got from ebay. Everything thing seemed to work pretty smooth.

Jug and top end painted up, too. Still need to clear coat the top end.

Should have some pics here in a day or two.
 
Re: CB360 Cafe Project *Engine Time*

Alright, the nice weather is here in KY, and I've been busy cleaning up my new yard that the PO let go to shit. Fortunately, between that and getting screamed at by my newly-wed pregnant wife, I've got to spend some time getting this engine closed up.


It all went pretty smooth. This tranny was a breeze compared to the dirt bike bottom ends I'm used to. Engines are always my favorite part of a build/rebuild. This one was fun. (Lets hope it works)


I have some SS socket head bolts to replace all of the phillips screws on the engine. Haven't swapped them out yet.


Some random engine pix...




Nice and clean


HPIM2309.jpg



HPIM2314.jpg



HPIM2316.jpg





All buttoned up...


HPIM2324.jpg



Does anyone else really dig the lightly rusted bolt/screw heads on the roughed up aluminum. I think it looks sweet.
 
Re: CB360 Cafe Project *Engine Time*

Love the look of that engine. I took all my side covers off on mine with the intent to wire wheel them down and then polish them up. I got them down to bare metal and decided that i liked the look so much i was going to keep it. Seems like you did something similar. It has sort of a roughed up look, but at the same time, doesn't look beaten up/ugly. I like the look of the semi rusty bolts on the bare aluminum. looks sick.
 
Re: CB360 Cafe Project *Engine Time*

Erskine, two weeks in and it's crossed my mind. It's like what my motorcycle safety instructor told me when I was 16 about crashing, "It's not IF, but WHEN!" Lol! Kidding of course....

Idordai, all I had on hand when I polished my cases/covers was a fine steel wire and a coarse brass wire wheel. Both took too much metal off, even just touching lightly. So, I didn't even use them. Every piece of aluminum on my bike so far is just paint stripped, 150 grit, then 400 grit polished. It leaves a nice brushed look. I'm not interested in anything shiny. I might go back over some of the stuff with some 400 wet, but I'm pleased for now.
 
Re: CB360 Cafe Project *Engine Time*

Great build you have going.
Keep up the good work, I'm enjoying the updates. :D
 
Re: CB360 Cafe Project *Engine Time*

Thanks.

Frame clean-up and electrical system will be next on the agenda.
 
Re: CB360 Cafe Project *Engine Time*


Got the sprocket cover shaped up.


Before...


Sprocket_Cover_Before.jpg





After...


HPIM2329.jpg





Not without function, though. The big holes allow access to the two bolts holding the sprocket on.




HPIM2326.jpg
 
Re: CB360 Cafe Project *Engine Time*

I like the holes, might have to do something similar with mine. If you ditch the ss bolts send em my way!

Bear with her, she's pregnant.

out
 
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