View Full Version : Advice wanted: engine swap or not?

07-14-2019, 01:30 PM
I have a dilemma: should I swap engines or not?

The situation is that my current engine (with 85kkm) has some issues:

Most serious is a rattle in neutral at low RPM, and under load at low RPM. I changed the clutch house bearing but that made no difference. My assessment is that a larger bearing in the gearbox is likely going bad. Fixing that would require an engine removal and splitting.
Engine is using a little oil, in the range of 1 liter every 8-10kkm
Shifting is clunky, especially compared to other Capoís. Finding neutral is really hard. (I did not do the oil jet swap from 60 to 40 yet)
The ground point on the front cylinder is helicoiled by the previous owner.
Itís time to check valve clearances
I want to inspect and clean cam chain tensioners.

I was able to buy a similar mileage engine with no known issues for less than the price of a gasket set. I had the intention of preparing this one and then swapping it. Since the engine is out of the bike itís easy to do valve check/adjustments et cetera.

Yesterday I was at the dealer and asked his opinion. He was pretty sure the problem with the low rpm rattle was due to some play between the clutch basked and the clutch gear on the primary drive. Something that will gradually get worse over the next 10k-20k. When your bike sounds a little bit like a ducati it's time to fix it. If this is really the case it would be a whole lot easier/quicker to just swap the primary drive from the donor block and be done with it.

Given the fact that Iím no professional and never done an engine swap I see some risks:

too difficult: may end up with a non working motorcycle
not necessary: just swapping clutch baskets would be good enough too
takes too long: I planned a bike holiday in 3 weeks

So that gives me 3 options

Proceed with engine swap
Only swap clutch
Donít swap anything and just ride, for now ;)

What do you guys recommend?

07-14-2019, 03:19 PM
If you knew what is was that was wrong with it and fixing was cheaper than a replacement engine, then yeah fix it. But when you're uncertain and you add in the oil consumption....me I'd swap it. I've never swapped a rotax aprilia but sure take your time and do as the manual says. Perhaps a futura motor!?

07-15-2019, 04:15 PM
Thanks the_toe_cutter. I tried to extract the clutch basket today, but it won't fit through the side panel. So far for a quick clutch change ;).

07-16-2019, 04:52 AM
Ride for now. Change the engine after your bike trip.

haga lout
07-16-2019, 01:46 PM
Grant swapped mine out in about 6 hours from ride in to ride out I’ve done one myself and it took me 2 days but not full days probably 10 hrs in total but I didn’t rush

07-16-2019, 03:49 PM
Like Nerald said.

Thing with repairing is unless you are prepared to go over everything then the next thing that goes becomes a real turd from a repeat effort standpoint.

Once the tank is off...

Will the bike make the trip as is? Do that. Then swap and futz with the old engine as you please.

07-17-2019, 12:15 PM
Ride to California. I'll give you my spare engine.

07-17-2019, 02:04 PM
Did I read spare engine? Decent shape and miles I presume?

07-17-2019, 07:16 PM
"Engine is using a little oil, in the range of 1 liter every 8-10kkm"
10kkm is (if my rusty metric conversion skills are correct) 6250 miles. I have never run that far between oil changes in any vehicle I have owned in 50+ years (nearing 100 bikes and more than a dozen cars/trucks in that time). A liter of oil in that mileage, I don't think I would be concerned about. A liter in 3,000 miles (my usual oil change interval) I have heard of, and might be concerned with.
I would not swap into an unknown engine just before a trip. Perhaps ride what you have on the trip, take it easy, and when you return, re-evaluate and decide which way to go.
Me, I would consider tearing the "new" engine down, at least pull the heads and have a look at heads, valves, cylinders and rings. If you bought it for less than the cost of a gasket set, then buy a gasket set, have a look inside and (depending on the results) install it after the trip...and take it easy until you trust it...and then enjoy.

07-24-2019, 07:12 PM
Did I read spare engine? Decent shape and miles I presume?

Good shape as far as I know. Came from a crashed bike near Santa Cruz ages ago, but there's no injury to the engine from the crash. Can't remember exact mileage, but I think it was in the 10k-15k range. I've never heard it run, but it was obviously running when its original chassis got hit.

Has wiring, ECU, etc. Coils too, I think. Since I bought it, nothing on mine has failed. Figures.

07-24-2019, 10:40 PM
It's like that, the part you have spares for will never fail. Possibilities if you want to part with it. I have so many spares just a frame and engine would make another bike, literally. I've been adding to the pile I got from Matt.