87aspy motor vs 86 aspy motor

[steve allen]

Okay, I have some issues with my 130,000 mile 87 aspy motor, (noises sounding like timing chain slapping everything) and found a great low mileage 86 aspy motor.....are they the same? Well the 86 motor be a direct plug and drive in my 87 aspencade?

[BigBro]

Not trying to second guess your assumptions but have to comment.

130K is about midway in mileage on these.

I have had my 1984 Interstate less than a year. When I got her she had a lot of slapping and rattling at idle.
Once I got above about 2200 or so RPM's she started sounding solid, adding a little choke really cleaned her up even more and on up she really sounded good.
So I knew I had a solid power plant but the low speed wasn't right. Told me fuel, timing, ignition most likely.

I rebuilt my carbs this winter (found a lot of issues) and did a good sync on the carbs after putting them back on.
Changed timing belts for comfort- timing was dead on anyway since you can't really change the electrical timing.

Added External Alternator ensures good volts to battery and new battery (my fault although it was 4 urs old and weak)

I have to say it is a world of difference today. Got her out for 2 short rides today, one pulling a 15% grade in 4th gear at 30 mph - it lugged but didn't balk, Other was pulling a couple kitsap penninsula hills at 45 in 4th, it would lug in 5th but too low for me so back to 4th.

I never heard any rattles, clacks or things that were noisey just the typical gearing whine.

What I am saying is that it might be an easier avenue to pursue with that engine than change out to still have a bad running engine due to the items like carbs, ignition volts, etc.

[steve allen]

When I bought this wing, it was a parts bike for the other the people had already sold. The noise I hear is as if you was hitting the engine case with a hammer and can feel it through out the bike. Yes, I know that real gas (ethanol free) makes alot of difference in performance, but the noise is still there. Everyone keeps saying I have bad knocking noise in motor and need to have it checked out. I also have tappet noise coming from left bank of motor as well. To pull motor and repair, cost is more than the 86 aspy motor with 61,000 miles I just bought. Heard it run, at 700rpm (very low for wing) no noises like my motor is doing. Motor revved up crisp and solid.

[admin]

As far as I know, 86 and 87 1200 Aspencade/Interstate carb type engines are almost identical with the SEi fuel injected engine being quite different. 85 carb engine will also work, but, 84 engine is quite different. A poorly done carb synch can often make the 1200 engine sound like it is knocking, you could try the carbs from the replacement engine to see if they make a desired difference before the engine swap. Without hearing your engine, it sounds to me like the oil pump/crank bearings have failed in your current engine. Often this happens because someone did not pay attention, immediately, to a leaking water pump which causes the anti freeze to destroy the oil pump and crank bearings. You can verify the oil pump issue by rigging some fittings on the engine and installing an oil pressure gauge. Typically, you won't see any appreciable oil pressure until the engine reaches 2000 RPM and even then it won't be very high, perhaps 5 to 10 psi above 5000 RPM (14 - 74 psi hot per Honda manual.) Realistically, should be in the 15 - 30 psi range. Oil pumps, if still available, cost about $700. and then you need engine gaskets for about another $200.+ and still you need crank bearings making it a much smarter move to just replace the engine with a good one for about $300. - $700.

[joe turner]

Hydro-locked engine, bent rod would give a sound like hitting block with a hammer.