New owner - ST1100 project

[DikkieDikkie]

Good morning,

First off I'll introduce myself, I'm Bas, 26 years old, and located in the Netherlands. Got my motorcycle license when I was 18, and I've only just realised the ST is my 10th(!) bike .

A few weeks ago I "purchased" my first 1996 ST1100 with an alleged 96k on the odometer, and with purchased I mean it was free. The previous owner had the distribution belt snap, and planning to fix it, he purchased a spare engine to swap. Unfortunately, he did not have much time (and possibly motivation) to do this, and got as far as taking off the fairings and draining the coolant.

I went to pick up the bike and engine, looking for a project bike to work on. And with a free bike (except for the 250€ it cost to pick it up), there's very little risk .

I've now disassembled the bike far enough to get the engine out. Unfortunately, upon closer inspection it appears the spare engine the last owner purchased, is from 1992. Since I dont want to deal with the 28A alternator (which also did not come with the spare engine), I have now elected to take off the cylinder heads of the currently installed engine, inspect for damage due to the belt snapping and if neccessary, swapping over the cylinder heads of the 1992 engine.

I have been wondering if there's any difference between the cylinder heads between these 2 engine's? Any help is much appreciated!

 

[ST1100Y]

... I have now elected to take off the cylinder heads of the currently installed engine, inspect for damage due to the belt snapping and if neccessary, swapping over the cylinder heads of the 1992 engine...

I seriously hope you haven't started dismantling that '92 engine yet !!!

Quality-wise were '92 till '94 the best years throughout all models at Honda, so instead of cracking that engine open, I'd carefully inspect it though, but use as is and only bolt the 40A alt from the '96 to it...

Besides this are there chances that you'll might find damaged piston crowns, connecting rods, bearings, etc... in the '96 engine as aftermath of the snapped timing belt... (which looks nasty BTW)

Kudos for the efforts, and happy hunting (for spares, at eBay and such )

 

[DikkieDikkie]

I seriously hope you haven't started dismantling that '92 engine yet !!!

Quality-wise were '92 till '94 the best years throughout all models at Honda, so instead of cracking that engine open, I'd carefully inspect it though, but use as is and only bolt the 40A alt from the '96 to it...

Besides this are there chances that you'll might find damaged piston crowns, connecting rods, bearings, etc... in the '96 engine as aftermath of the snapped timing belt... (which looks lasty BTW)

Kudos for the efforts, and happy hunting (for spares, at eBay and such )

So far ive taken off the cam off of the right side, and one headbolt (before realizing I desperately need a breaker bar), so no issues and I reckon I can bolt it back up (not ideal about the headbolt, but I'm hoping removing 1/6 headbolts didnt disturb the headgasket too much...). Does the alternator just easily bolt up? I thought I remembered reading something about an extra oil cooler, different hoses etc? Would love to hear!

And yes its really nasty in there... The waterpump seized and the belt got dragged over the pulley, making it nice and hot before snapping in the end

 

[ST1100Y]

If not done already (or having a hard-copy) I'd start by downloading this:

https://st1100-1300.wmco.org/st1100/Honda_ST1100_service_manual/Honda_ST1100_service_manual.pdf

Also highly helpful to locate part numbers:

https://www.cmsnl.com/honda-st1100-paneuropean-1992-n-european-direct-sales-kph_model4737/partslist/?ac_section=model&ac_q=st1100

The extra oil cooler came only in conjunction with the "flooded" (hence oil-cooled) 26A generator, and can remain in place/operation after the 40A upgrade (like on my '94...)

I'd also pull the rear wheel and check the conditions of the drive spline and hub dampers... you might find something there...

What I would suggest on the SC26 donor plant:
- compression test
- inspect/adjust valve clearances
- inspect/replace clutch friction plates
- inspect rebuild clutch cylinder
- replace all coolant water-pipe O-rings
- replace the two elbows on the engine heads (inboard)
- coolant stat, case O-ring and radiator cap
- replace all coolant lines
- inspect/replace t/belt, spanner- & idler pulley and water-pump
- 40A upgrade

It would be interesting to know how many km the donor engine has on it...
But since the '96 is blown, you've to go with what you have

And you'll also have the joys of overhauling the carbs; again I'd recommend to keep the OEM jets and just clean/ultrasonic them, as the Honda brass is far superior to any rebuild kits floating around...

 

[DikkieDikkie]

If not done already (or having a hard-copy) I'd start by downloading this:

http://[URL]https://st1100-1300.wmc...ervice_manual/Honda_ST1100_service_manual.pdf

[/URL]

Also highly helpful to locate part numbers:

http://[URL]https://www.cmsnl.com/h...l4737/partslist/?ac_section=model&ac_q=st1100

[/URL]

The extra oil cooler came only in conjunction with the "flooded" (hence oil-cooled) 26A generator, and can remain in place/operation after the 40A upgrade (like on my '94...)

I'd also pull the rear wheel and check the conditions of the drive spline and hub dampers... you might find something there...

What I would suggest on the SC26 donor plant:
- compression test
- inspect/adjust valve clearances
- inspect/replace clutch friction plates
- inspect rebuild clutch cylinder
- replace all coolant water-pipe O-rings
- replace the two elbows on the engine heads (inboard)
- coolant stat, case O-ring and radiator cap
- replace all coolant lines
- inspect/replace t/belt, spanner- & idler pulley and water-pump
- 40A upgrade

It would be interesting to know how many km the donor engine has on it...
But since the '96 is blown, you've to go with what you have

And you'll also have the joys of overhauling the carbs; again I'd recommend to keep the OEM jets and just clean/ultrasonic them, as the Honda brass is far superior to any rebuild kits floating around...

Thanks for the step by step write up! I'll see how far i get with it this weekend . If I discover anything worth mentioning Ill share it here. The 92 engine does not have the oil cooler previously mentioned, only the hoses going from the oil filter to where the oil cooler would be...

The card attached to the spare engine (bought from Baboon) said it had somewhere around 92k kilometers, so not far from what the odometer displays on the bike. And if well maintained, plenty more life in it

 

[ST1100Y]

If I discover anything worth mentioning Ill share it here. The 92 engine does not have the oil cooler previously mentioned, only the hoses going from the oil filter to where the oil cooler would be...

Ah! So someone removed it from the case...
You'll have to alter/plug the connection from the '92 water-pump... (compare the plumbing with the blown '96 engine to figure it out)

The card attached to the spare engine (bought from Baboon) said it had somewhere around 92k kilometers, so not far from what the odometer displays on the bike. And if well maintained, plenty more life in it

Indeed, barely broken in... (those things can last 400,000km and beyond...)

 

[Uncle Phil]

That is one of the few ST1100s I have heard of that the timing belt broke.
What usually happens is one of the belt tensioner/pulleys go bad or the water pump and that thrashes the engine (BTDT).
Go with Martin's advice and do the engine swap and the alternator change.
You'll be happy you did!