There have been a few questions lately about if and how something like this can be done, so Kreylyn and I decided to get some pictures and post about the process. Previously, we'd done a post 600 into a pre 600 swap, but that involved beer, a house warming party and other unmentionables so there weren't any pictures and is probably better left to memory.
So, first you need a motor to put in. I bought a 1993 750 last fall for $225. It was a more or less complete bike, meaning most of the pieces were included in the purchase. Previous owner had thought it needed a valve adjustment and couldn't get it to run correctly.
It is/was very important to me to know that the motor was good before actually putting it in my bike. I've seen a couple people here that have swap a motor with problems for an unknown motor and then couldn't get any of them to run right. So we did a lot of work and testing on this 750 motor before the swap.
First problem was it had a broken rocker arm. We replaced that and pulled the head to inspect every thing for damage. Put it back together and adjusted the valve clearances.
Then the carbs were rebuilt and a Factory Pro jet kit installed. The bike had K&N pods with it and the needles that came in the carbs were Dynojet. We know at the time and place the bike was sold there was a dealer really anxious to put stage 3 kits and pods on these Kat 750's, so that wasn't a surprise.
Everything was then mounted up in a frame and connected enough for us to test the motor. We noticed a bit of back fire on cylinder 2 so it all came apart and the head went to visit some cousins for a few weeks. We had everything tested and checked and machined and what not (I figure I don't need to know this part as I am blessed to have trustworthy people in my life who are experts in this field) to make sure it was right. This delayed the swap by a few weeks but was worth it and the money for my piece of mind.
Now every thing went back into the mock up frame to be tested. Tim got the exhaust mocked up on that frame and everything together so it would fire up and run. I have to admit, I bought the exhaust can because I thought it was pretty. I expected it to be stupid, obnoxious and loud. I don't like the sound of exhausts that my husband and other guys like, I like quiet ones. Well this exhaust isn't quiet, but it sounds damn sexy, not obnoxious. Every time we fired up the test system I giggled. Seriously full on giggled.
But enough about that, the carbs were seated and rough synced on the test frame and so we have the motor as known good as we can. The transmission is an unknown at this point, but if it proves to be problematic, we will put my 600 engine back in while we research/fix that.
Here's the motor going in:
The bike it's going to:
Fairing off. You might not need to remove the tail fairings, but it makes it so much easier to get to the wiring harness connections and such. Plus it gets them out of the way of stray tools and other dropped items.
We are replacing the forks at the same time. Once again, you don't NEED to take the front end off, but it makes it MUCH easier to get the engine in and out. Plus having the bike free hanging like this makes it easier to got it moved around.
These mover's dollies are awesome for moving/storing engines on. Unfortunately, we only have one available for this project so it has to do double duty.
And the motor comes right out and rolls away.
New motor is out of it's the frame.
We have been at it for 2 hours at this point.
The 750 was a California model, so it had the emission crap. We removed and blocked off the California part of the carbs, but these likes need to be removed and blocked off.
And done...
New motor lined up...
And it's in!
The header and mid pipe is on as well, just the picture that shows that didn't come out worth a darn.
A few things to mention.
I have a new chain and sprocket so we were sure to remove the front sprocket BEFORE dropping the engine. If I didn't have maybe 200 miles on the chain and sprocket set I would have probably waited to do the swap and just put a new set on.
The side stand safety switch on the 750 had a different plug in than the 600. So we swapped that out, I had to swap the side stand anyway, my bike is lowered 1.75" so it needs the modified side stand or it falls over.
All told we worked on it from 4:00 pm to 10:30 pm with stopping about an hour for dinner and we lost about 1.5 hours going backwards for the side stand stuff. So about 4 hours for the actual swap with 2 people.
Tonight, We are going to put the front end on, put the plastics back on, hang the muffler, fine tune the carbs, and hopefully take it for a test ride.
So, first you need a motor to put in. I bought a 1993 750 last fall for $225. It was a more or less complete bike, meaning most of the pieces were included in the purchase. Previous owner had thought it needed a valve adjustment and couldn't get it to run correctly.
It is/was very important to me to know that the motor was good before actually putting it in my bike. I've seen a couple people here that have swap a motor with problems for an unknown motor and then couldn't get any of them to run right. So we did a lot of work and testing on this 750 motor before the swap.
First problem was it had a broken rocker arm. We replaced that and pulled the head to inspect every thing for damage. Put it back together and adjusted the valve clearances.
Then the carbs were rebuilt and a Factory Pro jet kit installed. The bike had K&N pods with it and the needles that came in the carbs were Dynojet. We know at the time and place the bike was sold there was a dealer really anxious to put stage 3 kits and pods on these Kat 750's, so that wasn't a surprise.
Everything was then mounted up in a frame and connected enough for us to test the motor. We noticed a bit of back fire on cylinder 2 so it all came apart and the head went to visit some cousins for a few weeks. We had everything tested and checked and machined and what not (I figure I don't need to know this part as I am blessed to have trustworthy people in my life who are experts in this field) to make sure it was right. This delayed the swap by a few weeks but was worth it and the money for my piece of mind.
Now every thing went back into the mock up frame to be tested. Tim got the exhaust mocked up on that frame and everything together so it would fire up and run. I have to admit, I bought the exhaust can because I thought it was pretty. I expected it to be stupid, obnoxious and loud. I don't like the sound of exhausts that my husband and other guys like, I like quiet ones. Well this exhaust isn't quiet, but it sounds damn sexy, not obnoxious. Every time we fired up the test system I giggled. Seriously full on giggled.
But enough about that, the carbs were seated and rough synced on the test frame and so we have the motor as known good as we can. The transmission is an unknown at this point, but if it proves to be problematic, we will put my 600 engine back in while we research/fix that.
Here's the motor going in:
The bike it's going to:
Fairing off. You might not need to remove the tail fairings, but it makes it so much easier to get to the wiring harness connections and such. Plus it gets them out of the way of stray tools and other dropped items.
We are replacing the forks at the same time. Once again, you don't NEED to take the front end off, but it makes it MUCH easier to get the engine in and out. Plus having the bike free hanging like this makes it easier to got it moved around.
These mover's dollies are awesome for moving/storing engines on. Unfortunately, we only have one available for this project so it has to do double duty.
And the motor comes right out and rolls away.
New motor is out of it's the frame.
We have been at it for 2 hours at this point.
The 750 was a California model, so it had the emission crap. We removed and blocked off the California part of the carbs, but these likes need to be removed and blocked off.
And done...
New motor lined up...
And it's in!
The header and mid pipe is on as well, just the picture that shows that didn't come out worth a darn.
A few things to mention.
I have a new chain and sprocket so we were sure to remove the front sprocket BEFORE dropping the engine. If I didn't have maybe 200 miles on the chain and sprocket set I would have probably waited to do the swap and just put a new set on.
The side stand safety switch on the 750 had a different plug in than the 600. So we swapped that out, I had to swap the side stand anyway, my bike is lowered 1.75" so it needs the modified side stand or it falls over.
All told we worked on it from 4:00 pm to 10:30 pm with stopping about an hour for dinner and we lost about 1.5 hours going backwards for the side stand stuff. So about 4 hours for the actual swap with 2 people.
Tonight, We are going to put the front end on, put the plastics back on, hang the muffler, fine tune the carbs, and hopefully take it for a test ride.
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