Wayne's Triumph Trident 750 engine overhaul by GrandPaul

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This begins another overhaul project, this time a classic Triumph Trident 750 triple.

Wayne sent me the lump with the top end already disassembled...

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So, first came the removal of the timing cover; not too much trash, but definitely looking dirty and baked-

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It's a real jigsaw puzzle as to whcih sub-assemblies need to come off before you can split off the outer crankcase sections from the center section.

Tranny cover off; not too bad at all, no sludge or crud-
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Oil line conections were munged by postal mishandling. (It took 3 weeks for the box to arrive due to delivery errors; I can only imagine how much it was shuffled around)
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Right side outer cover off with cams in place (cam bushings have zero play, VERY smooth)
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Oil filter was at the far end of it's life-
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Over to the other side, primary cover removed-
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Strange grunt in there...
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Another jigsaw puzzle removing the clutch housing section to get to the left side outer crankcase cover...
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Kinda messy inside the clutch containment, but no bad suprises-
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Even the drive sprocket was in good shape!
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Left side crankcase outer cover finally off; again, no suprises-
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So far, so good!
 
Hmmmmmm... serial numbered crank.

Note crank caps have "D" (Drive side / Left) and "T" (Timing side / Right) markings, with stampings oriented toward the front of the engine-
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Down to the heart of the matter...
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Rod bearings shell halves, from Left to right as seated on the bike-
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Looks pretty good, typical wear...
 
Crank journals all look good, just need a simple polishing, no grinding-

Left rod journal, left main journal, center rod journal-
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(part of center rod journal), right main journal, right rod journal-
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Lower mains showing mildly excessive wear down to the copper core of the bearing shells on the right side, left side okay-
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Upper main caps, wear equal to lower halves-
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Tranny shots later, it all came out clean, so not much to show until close inspection.
 
Great post thanks Paul.

Been 36 years since I have seen the insides of a Trident. Bought one in 1975 with a hole in the centre pistion and rebuilt it with sprint cams, high compression pistions, port job, re radiused cam followers, light clutch etc. Raced the thing back then with excellent results until one dark and stormy night some f***er decided it would be better in his shed. Turned up about 3 months later in a very abused state minus engine and frame numbers and the police had forensically identified it as belonging to me. The "receiver" spent 3 months locked up for his crime. Should have spent another year inside for abusing such a fine motorcycle. The bottom end is vertually indestructable. If I recall correctly, mine would rev beyond 9,000 rpm. It gave you a kick in the back side at 4000 rpm as it came onto the cam. The 3 into one race exhaust was pure music. Still makes me smile!
 
Oh yeah, Tridents are mighty fine. I have a '74 T150, and a '75 T160 e-start.

The mechanical Banshee howl as they come on the cams raises the hair on the back of my neck and arms (it's even doing it now just thinking about it, does that every time). Pure mechanical music.
 
Yeah, it's pretty amazing to find out there is precious litle related to "pasting" a center cylinder in betwen the jugs of a 500.

Differences top to bottom:

1. Triple rockerboxes not even a vague resemblance; rockers, valves, cams, etc. of course additional qty.
2. 3-pot head not even close to 500 +1 pot (cylinders close enough, not totally different)
3. alternator on right, in timing chest
4. 3-piece crankcases
5. one-piece crank
6. dual crank main bearings blocks
7. COMPLETELY different clutch assembly with multiple containment sections in wierd configuration
8. Oil filter setup internal to engine
9. Oil sump setup with strainer like the old pre-unit engines
10. Timing idler gear on a huge shaft with retainer circlip (nice touch)
Tranny is virtually identical to Bonneville, both of which do NOT resemble the 500 very much at all.

The engine is NOT 50% heavier than a 500, it's about 100% heavier than a 650!
 

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