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twinegar
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Post by twinegar »

I replaced a dented carb cap yesterday which fixed the poor running and took a long ride. It runs great and if I go easy on the throttle very little oil burns through. I have to go through the new break in procedure because of the new rings and cylinders anyway. When pushing the bike around the garage I can hear the chain popping slightly on the front sprocket so a replacement is probably in order. The sprocket looks good but the chain has reached the replace mark on the label. I wonder what is next.
CBX #1 - http://www.spookytoms.com/SpookyTom-CBX-79-1-4.html
CBX #2 - http://www.spookytoms.com/SpookyTom-CBX-79-2-5.html
http://www.spookytoms.com/SpookyTom-MTRCCLSTF.html

"66CL160, 68CL125A, 68CL450, 69CL125A, 69CB750, 71CB450, 71CB500, 71CB750, 72CB350F, 72CB750, 74CB750, 75CL360, 75CB550, 75CB750, 76CB750, 79CB750, 79CBX, 79CBX, 80CBX, 82CB750, 84VF700S 05HDSPORTSTER1200ROADSTER"

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Post by alimey4u2 »

Coming along nicely, don't give up...... :wink:
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twinegar
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Post by twinegar »

I can't leave it alone. I will be removing the head on CBX#1 again this week and will have a professional do the valve guides on #1 cylinder. Hopefully the base o'rings are the problem and I can have it together and in good shape soon. I can pull the plug and see oil glistening on top the piston. A plug fouled after about 90 miles with burnt oil bridging the gap between the electrodes.

With 24K would you replace the cam chains? I am hearing some noise that sounds like a loose chain but I have already adjusted them. Is there something that I should replace or take a look at?
http://www.spookytoms.com/SpookyTom-MTRCCLSTF.html

"66CL160, 68CL125A, 68CL450, 69CL125A, 69CB750, 71CB450, 71CB500, 71CB750, 72CB350F, 72CB750, 74CB750, 75CL360, 75CB550, 75CB750, 76CB750, 79CB750, 79CBX, 79CBX, 80CBX, 82CB750, 84VF700S 05HDSPORTSTER1200ROADSTER"

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Post by alimey4u2 »

The cam chain is understressed due to the valve springs assisting each other. 24k shouldn't be a problem, I wouldn't go through the problem of splitting the crank case to test but do a visual inspection. Good time to check the slippers on the tensioners though....
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twinegar
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Post by twinegar »

I am glad you said that. I wasn't wanting to crack the case. I have to do that on my 74 750 to replace the sprocket shaft bearings and figure one case per year is plenty. On the CBX I am going to try to find a mechanic that will replace the valve guide o'rings on cylinder 1 without doing the rest. The other 5 spark plugs look like they are supposed to so there is no sense in paying for new parts and labor that the engine doesn't need.

What do I look for when checking the slippers and tensioners?
http://www.spookytoms.com/SpookyTom-MTRCCLSTF.html

"66CL160, 68CL125A, 68CL450, 69CL125A, 69CB750, 71CB450, 71CB500, 71CB750, 72CB350F, 72CB750, 74CB750, 75CL360, 75CB550, 75CB750, 76CB750, 79CB750, 79CBX, 79CBX, 80CBX, 82CB750, 84VF700S 05HDSPORTSTER1200ROADSTER"

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Post by alimey4u2 »

twinegar wrote:What do I look for when checking the slippers and tensioners?
Just general wear or de-lamination of the plastic/rubber slippers. it will be quite obvious. Make sure the mechanisms are smooth & springy in taking up the slack...Did you say what mileage ??
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Post by twinegar »

.......mileage is 24K
http://www.spookytoms.com/SpookyTom-MTRCCLSTF.html

"66CL160, 68CL125A, 68CL450, 69CL125A, 69CB750, 71CB450, 71CB500, 71CB750, 72CB350F, 72CB750, 74CB750, 75CL360, 75CB550, 75CB750, 76CB750, 79CB750, 79CBX, 79CBX, 80CBX, 82CB750, 84VF700S 05HDSPORTSTER1200ROADSTER"

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Post by alimey4u2 »

twinegar wrote:.......mileage is 24K
At 24k I wouldn't thing wear would be an issue but age may...
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Post by twinegar »

Just stripped the black paint from the replacement head with aircraft paint stripper. The head was advertised as being from a 81 with less than 200 miles on the odo. I was skeptical at first but judging from the condition of the combustion chamber, exhaust ports and cam chain tensioners and slipper I would have to agree it was from a low mileage engine.

The new head didn't come with the cams but does have the lifters. My intension is to use the lifter cans and cams from the old engine installing the cans on the same valves in the same order as they came off. I will also replace all the tensioners and slipper with the low mileage ones.

Anyone care to weigh in with suggestions or comments?
http://www.spookytoms.com/SpookyTom-MTRCCLSTF.html

"66CL160, 68CL125A, 68CL450, 69CL125A, 69CB750, 71CB450, 71CB500, 71CB750, 72CB350F, 72CB750, 74CB750, 75CL360, 75CB550, 75CB750, 76CB750, 79CB750, 79CBX, 79CBX, 80CBX, 82CB750, 84VF700S 05HDSPORTSTER1200ROADSTER"

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Post by alimey4u2 »

Just follow the shop manual through the finite steps & details, do not deviate from the procedure ( bypass a step.) Take care installing the cam pairs. It has been know to install the pairs 180 deg out of phase & you end up with a six cylinder motorcycle with the power strokes of a three cylinder. It absolutely Honks off the line but frags the cam chain very quickly. Plastigage all the cam bearings to ensure correct tolerance & alignment....DO NOT rotate the engine with ANY of the shims OUT ! You will carve the edges of the cams in the buckets. Prelube the cams with the recommended lube upon assembly & top the cam oil wells up with engine oil.
Apart from that take your time & be methodical.... :wink:

I'm sure more advice with things that I have missed will follow....
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Post by twinegar »

The camshaft caps came with the new head and are matched to the head. I shouldn't need the plastigage should I?
http://www.spookytoms.com/SpookyTom-MTRCCLSTF.html

"66CL160, 68CL125A, 68CL450, 69CL125A, 69CB750, 71CB450, 71CB500, 71CB750, 72CB350F, 72CB750, 74CB750, 75CL360, 75CB550, 75CB750, 76CB750, 79CB750, 79CBX, 79CBX, 80CBX, 82CB750, 84VF700S 05HDSPORTSTER1200ROADSTER"

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Post by alimey4u2 »

twinegar wrote:The camshaft caps came with the new head and are matched to the head. I shouldn't need the plastigage should I?
That is a moot point twinegar but if there is a problem with the donor cam ( not straight as an example) you could end up trashing the head ? Worn cam cap bearing surfaces ? Simple task with plastigage being cheap, just a little time consuming. When Mike sold me a 79 cam I checked it just to be safe...but then I can be anal at times.. :oops:

What do you other guys think ??
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Post by alimey4u2 »

Something I forgot to tell you, just a word of caution....

A while back I opened my engine to do a valve clearance check & noticed that one of the cam cap bolts was loose. Upon examination I found 3 of them were sheared. I know I torqued them properly !! Discussing this with a Honda mechanic I was advised that this was not uncommon. I then upgraded all of my cam cap bolts to aftermarket high tensile. Not had a problem since....

NOTE: I am running performance valve springs

Watch out for your cam cap bolts going soft on torqueing...Dont forget torque numbers are for "dry" bolts...
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twinegar
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Post by twinegar »

Where did you get the replacement cap bolts. I had several that were bad the last time around.
http://www.spookytoms.com/SpookyTom-MTRCCLSTF.html

"66CL160, 68CL125A, 68CL450, 69CL125A, 69CB750, 71CB450, 71CB500, 71CB750, 72CB350F, 72CB750, 74CB750, 75CL360, 75CB550, 75CB750, 76CB750, 79CB750, 79CBX, 79CBX, 80CBX, 82CB750, 84VF700S 05HDSPORTSTER1200ROADSTER"

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Post by alimey4u2 »

Summit Racing, ARP fasteners.

The shoulder (unthreaded part) was a fraction too long,( only ones available) so I used small ( but thick) high tensile washers beneath each bolt head. I got them from McMaster Carr. You can't cut a thread longer on these bolts as they are rolled threads & you will weaken them.
The cam cover just touched in places ( the middle caps with the oil fittings) so I Dremeled a little clearance in the cover in places. Put a dab of PlayDough on & closed the cam cover up to make sure all were clearing OK.....
The bolts are full diameter & not "waisted" like the stock bolts. I thought this may restrict oil flow to the cams so I did several tests with the cam cover open & all was well....

Whomever gets this engine when I die will think WTF !!!... :lol:
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