Anybody Here Ever Replaced A ST1100 Engine?

Here is a video - the bike was mostly torn down though before the engine was removed. There may be some useful info though.

 
Just from a standpoint of getting to know the lay of the land, I think I'd pull the donor engine first.

And I'd see if anyone locally has a 2T engine hoist you can borrow to pull the frame and then move the engine. They weren't light even when we were 22.
 
Something else to consider.

I know of one other situation where an ST1100 had a water pump failure, the bike had approximately 250 000 miles on it when the water pump bearing seized, leading to the derailment of the timing belt, which in turn lead to the valve timing going out. The upshot was sixteen bent valves, a couple of broken valve guides and a set of pistons with virtually not a mark on them.

Like you the owner had a spare engine, previously purchased for it's gearbox, so simply used the heads (and water pump) from the spare engine to replace the damaged ones. Last I heard of that bike it was running in excess of 285 000 miles so I guess it was a success.

I only offer this as an example of course and your damage situation may be very different, but if it is possible it might entail far less work.
 
STinkers said:
Something else to consider.

I know of one other situation where an ST1100 had a water pump failure, the bike had approximately 250 000 miles on it when the water pump bearing seized, leading to the derailment of the timing belt, which in turn lead to the valve timing going out. The upshot was sixteen bent valves, a couple of broken valve guides and a set of pistons with virtually not a mark on them.

Like you the owner had a spare engine, previously purchased for it's gearbox, so simply used the heads (and water pump) from the spare engine to replace the damaged ones. Last I heard of that bike it was running in excess of 285 000 miles so I guess it was a success.

I only offer this as an example of course and your damage situation may be very different, but if it is possible it might entail far less work.
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This actually sounds like it may be the best option assuming the pistons aren’t damaged. You know/assume your SweetTreat block is in good condition as you’ve done all the maintenance while you don’t know everything about the donor engine (and it’s unlikely you can fire up the donor engine to see if it runs properly on an engine stand- also, was the donor bike on its side as a donor, such that maybe it was running and oil starved? Again, just a thought). If you have just have valve and water pump failure, I would agree with the above opinion, as it’s much less work. How about pull the spark plugs, use a bore scope (not sure if you can rent one vs buying one), and have a look inside, and at least that way you can assess you current ST‘s engine condition.
 
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I don't disagree with the idea, but easier? :shrug1:
But, it might be a good idea to take the heads off anyway prior to removal/head change :think1:.
What do two ST11 heads weigh......quite a bit I would think.
I would think of it as nothing ventured/nothing gained.
Upt'North.
 
Watched the video, removing the engine looks tedious and it's heavy + the bike was stripped, just a frame. Installing an engine would be much more difficult I think as everything has to line up perfectly to bolt it in + you probably need strip off a few things for access. I'd go with pulling the heads to see what was damaged and if just replacing the water pump and heads from the donor engine along with a new belt would work. Sound like significantly less work to me + you're not going to get a hernia or sprained back trying to muscle around a 300 lb deadweight engine.
 
We move a lot of stuff at work with gantries and chainfalls. Dunno if you have suitable lifting points nearby, or maybe build a A-frame setup. 300lbs isn't real heavy, just awkward.

RT
 
How perverse to take the engine on the left side . I had imagined laying the engine on the left ,probably because I get on a bike from the left side . The wheels are heavy items so leave them attached until on the side and then take the wheels off.The frame removal will not be so difficult . Knowing the attachment details is important but mainly the parts that might go bang in your spine are the main problem . Hard to keep your back straight for heavy lifting leaning over a sick 1100 . There must be steel tripod frames for this kind of lifting . See your friendly garage welder for a simple triangulation one off . One back of an envelope should explain the design .
 
Having done headwork on various V8 engines in my 'motorhead' days, I believe I'll pass on the 'head' idea. With cars, I have rebuilt engines, swapped engines (from a 70 malibu to a 64 pickup truck - V8 replaced a 6), replaced transmissions, rebuilt suspensions, brake systems, etc. In one case I had two pickup trucks - one a standard and one an automatic. When they came back out of my garage, the automatic was a standard and the standard was an automatic (hanging clutch pedals, swapping shifting mechanisms, etc.). I can do all sorts of 'mechanic' work but it's not my favorite thing to do. ;)

I would have to pull the heads on the original engine just to see if there is any damage and then pull the heads from an existing engine and buy all the gaskets, seals, etc. and then install them. And when an engine 'dies' hard like this one did at speed, there is no telling what else got damaged/weakened/tweaked in the process that you can't see. Dealing with heavy objects is something I've done many times over by myself so that part doesn't bother me. What is good is when someone has done this very thing says, "Oh by the way, if you do ...... it will go a lot easier" or "Watch out for ....." or "Don't forget to ....". I want to minimize the 'disassembly' of her since that means less to put back together but not to the point that makes the job near impossible. From what I can see if you have a 'platform' level with the frame to slide the engine out and in, you are miles ahead of the game. ;) I happen to work for a company that can do custom metal fabrication, so any jigs I need I have a solution. As Chuck said, George and Danny did one in ACL's work shop at Moonshine one year so there is hope for me! :biggrin: Since I still have 3 'runners' and other projects I have to do first, I'm in no big hurry. So I have lots of time to gather information and ideas so keep them coming. And I do hope to document the process for anyone else that faces this chore.
 
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Uncle Phil said:
From what I can find, the engine weighs a little north of 300 lbs according to those that have done it.
I've got some time before I can do it so I am researching it ahead of time.
It comes out the left side per the manual so I am figuring a furniture dolly blocked up should work to move it onto.
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Do you have a motorcycle lift like one of these?

1500 lb. Steel ATV/Motorcycle Lift (harborfreight.com)

You will be able to raise it up to the motor, block it if needed, and then lower it out of the frame after the sub comes off. Wheel it out of the way. When you put the replacement motor in, you can raise and lower it just enough to get the bolts through everything.
 
I have one of those - totally worth the money but I find the ram won't stay extended for any length of time, so plan to use the safety catches or something like wood blocks for support. It also works great as a lift to slide a double oven in and out of a wall.
I'm not sure how you'd keep an engine from falling off once free from the frame, though. Straps and some sort of cradle?
 
Smudgemo said:
I have one of those - totally worth the money but I find the ram won't stay extended for any length of time, so plan to use the safety catches or something like wood blocks for support. It also works great as a lift to slide a double oven in and out of a wall.
I'm not sure how you'd keep an engine from falling off once free from the frame, though. Straps and some sort of cradle?
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Thanks for that information. I guess I will have to wander over and take a look see (and hopefully catch a coupon along the way to get a better discount!).
 
snowmoer said:
Do you have a motorcycle lift like one of these?

1500 lb. Steel ATV/Motorcycle Lift (harborfreight.com)

You will be able to raise it up to the motor, block it if needed, and then lower it out of the frame after the sub comes off. Wheel it out of the way. When you put the replacement motor in, you can raise and lower it just enough to get the bolts through everything.
Click to expand...
I had one of these from HF. It didnt hold up well. Spend a few more $ and opt for the aluminum upgraded version.
 
UP: Delboy's garage just posted a utube video on reinstalling a rebuilt sportster engine into the frame. Don't know how applicable it would be in your project, but it's worth a look.
 
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