Engine Swap. Gen 2 to Gen 1

mech 1 twa · May 11, 2015

I was having gear box problems 05, mostly 4th .

Decided to replace complete engine with lower mileage Gen 2 2007 21,000 miles.

Researched differences and found only 3 problems to overcome.

1 neutral switch is missing. 2 left lower engine stay, mount different. 3 Connector from low oil sending unit different.

Neutral switch is missing Gen 2. Has a switch for gear position, 6 wire harness lower left by shift shaft.

Testing this switch found a ground on black wire in neutral position.

Crimped on a male bullet connector to black wire plugged into wire harness now have a neutral, ground signal.

Ordered a Gen 2 left lower engine sway, mount. Bolts to frame with no problems. $ 10 Part.

Crimped on bullet connector from oil sensor, plugged it in . oil light is out.

THIS is a easy swap, If you think replacing engine is easy. Its not have about 18 hours in this. mostly by myself.

Must use all Gen 1 parts from old engine, Throttle body, speed sensor, etc. Speed sensor works from gear in transmission, hole is there just install it.

Put 190 miles on it today work perfectly.

TripperMike · May 11, 2015

Nice going! That should give a lot of Gen 1's out there some extended life.

TomInPA · May 11, 2015

Wow, that's great you put this together. Any chance you can post some pictures of the key differences? Neutral switch, the engine sway mount, oil sensor. Good job. this usually requires abundant video, pictures and coaching from Yamafitter and Ionbeam. Of course it's not too hard to beat the time DCarver has in doing engine changes.

PapaUtah · May 11, 2015

Another pioneer blazing a trail for their fellow riders!!! Thank you for your service!!!

Auburn · May 11, 2015

Awesome, great to know info.

radiummadman · May 11, 2015

reminds me of the Johnny Cash song about building a Cadillac with all the parts he stole while working in a Caddy plant, "One Piece at a time".

mech 1 twa · May 11, 2015

I only took a few photos with my phone for reference of where things were.

2 simple wiring changes are needed to the Gen 2 sensors. Black wire 6 pin from gear sensor switch, cut and pined to harness Gen 1. neutral switch connector. Wire from oil level sensor cut and pined to stock harness. no damage to

Gen 1 harness.

Left lower engine stay-mount needs replacement. Bolt holes in engine are different. Triangular mount near shift shaft area. 2005 is longer, Gen 2 is a perfect triangle shape. Bolts to frame with new mount. Frame has a different part # but everything fits perfectly.

This is an 2005A ABS Used engine removed from 2007A

Canadian FJR · May 11, 2015

What gearbox issues were you having? What was 4th doing (not doing)?

Canadian FJR

mech 1 twa · May 11, 2015

Worn gear dogs. Harder to Up shift at higher RPM's.

Rough shift, up-down. Didn't drop out of gear, no noise.

Needed some parts. I felt it was cheaper and easer to find-replace with newer engine.

2007 engine has a different sound to it. Less whine at idle, when cold.

escapefjrtist · May 12, 2015

Nice work, good to know the generation swap is fairly painless.

--G

SkooterG · May 12, 2015

Nice! Great info to know. You get a gold star for being the first to set the learning curve.

Many years ago a trusted tech told me the only thing stopping a direct swap of engines between Gen I and Gen II was the VSS - Vehicle Speed Sensor, or more specifically how the two different Gens did it differently. I take it the VSS was not an issue?

mcatrophy · May 12, 2015

SkooterG said:
...Many years ago a trusted tech told me the only thing stopping a direct swap of engines between Gen I and Gen II was the VSS - Vehicle Speed Sensor, or more specifically how the two different Gens did it differently. I take it the VSS was not an issue?

In his first post, the OP says "Must use all Gen 1 parts from old engine, Throttle body, speed sensor, etc. Speed sensor works from gear in transmission, hole is there just install it.".

SkooterG · May 12, 2015

mcatrophy said:
SkooterG said:

...

Many years ago a trusted tech told me the only thing stopping a direct swap of engines between Gen I and Gen II was the VSS - Vehicle Speed Sensor, or more specifically how the two different Gens did it differently. I take it the VSS was not an issue?

Click to expand...

In his first post, the OP says "Must use all Gen 1 parts from old engine, Throttle body, speed sensor, etc. Speed sensor works from gear in transmission, hole is there just install it.".

I guess I wasn't clear enough. According to my tech where and how the speed signal was dectected was not the same on the two Gen engines and was not easily adaptable.

He must have been wrong since the OP didn't mention anything about it.

mcatrophy · May 12, 2015

SkooterG said:
mcatrophy said:

SkooterG said:

...

Many years ago a trusted tech told me the only thing stopping a direct swap of engines between Gen I and Gen II was the VSS - Vehicle Speed Sensor, or more specifically how the two different Gens did it differently. I take it the VSS was not an issue?

Click to expand...

In his first post, the OP says "Must use all Gen 1 parts from old engine, Throttle body, speed sensor, etc. Speed sensor works from gear in transmission, hole is there just install it.".

Click to expand...

I guess I wasn't clear enough. According to my tech where and how the speed signal was dectected was not the same on the two Gen engines and was not easily adaptable.

He must have been wrong since the OP didn't mention anything about it.

It's the GenII (and III) that take the speed from the rear wheel. I'd guess a GenII speed signal wouldn't work into a GenI ECU. Even if the electrical signal was OK, the frequency (pulses per mile) would be very different.

The OP very sensibly tried for his original GenI sensor plugged into the Gen1 engine, presumably picking up the speed from the teeth of a gear wheel, or maybe there's a dedicated toothed wheel for it that was continued into the GenII gearbox.

wheatonFJR · May 12, 2015

But does the thing still wheelie?

It is a Gen 2 engine after all.

wingshot · May 12, 2015

Awesome, now my options are increased exponentially for keeping my 05ABS. Thanks for making the effort.

wfooshee · May 12, 2015

The wheel that the speed sensor counts teeth on has 37 teeth in a Gen-II, and 36 teeth in a Gen-I. That slighty taller final ratio is going to reduce the pulse-per-mile count by almost 3 percent. The bike will be going just that tad faster than the speedometer reading, kind of like putting oversize tires on your car or truck.

OTOH, that less-than-three percent may be a smaller factor than the regular speedometer error.....

mech 1 twa · May 13, 2015

Checked speedometer against Garmin 550 at 80 mph.

Speedo 77-78 mph around 3% I knew there was a difference, can live with that.

Speed sensor is a direct bolt in, no modifications needed.

2 things i've noticed about newer engine.

My clutch always had a minor chatter, Gen 2 is smooth. Clutch engagement is further from the bar, using Gen 1 slave.. Stalled it the 1st time pulling away.

Gear whine from engine on fast idle is almost silent, Gen 1 had louder whine. Sound like 2 different engines.

Geezer · May 13, 2015

Does this mean that you get the additional wattage available from the stator on the Gen 2 engine? That would be a nice benefit.

Engine Swap. Gen 2 to Gen 1

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