I just scored a 2002 F4i complete motor for my 2003 with a dying tranny.

I got the '03 a month or so and didn't find, till I rode away...hard...that the 2nd gear was slipping in and out under hard accel..I went on ebay and bought the internals to fix the gearbox over the winter...not looking forward to that...but then my local forum I spied a low mile 2002 parting out sort of near me...so I offered and he took the offer...When I went to get it it ended up being really a lot more than the engine and trans...It came with the right clip on complete with throttle and cables and switchgear, MC front brakes hanging...radiator on, kickstand on, exhaust on throttle bodies on, hoses on everything almost complete...Amazing for $375

So I am swapping the whole lump in there tomorrow....He says it ran just great before he rear ended a car....We shall see...I just hated riding a bike without a usable second gear....
Don Hanson

 

I've dropped my motor and replaced it before its not the most fun to do but its not too bad. Use the best and cleanest parts of the two, like my new motor came with throttle bodies and thermostat but it didn't look as good as the old so I used the ones off my old motor. Also a thing that helped a lot is every bolt that came out was labeled and every electrical wire was labeled numerical. Keeps everything in line when plugging it back up. Have fun with it, I suggest you call a few buddies to help you out. Good luck and you got a good deal.

 

I use my camera to document the connections (hoses and wires) when I swap a complex motor set up. I spent yesterday getting the replacement motor ready and making those 'special tools' to get the motor mount washers off... I simply 'free-handed' some extra sockets with my dremel tool and cutting wheels.. ~$100 for Honda's wrenches.....that was too expensive for something to use only once or twice...

My least favorite part of working on a fully faired sport bike is removing and replacing the bodywork....It seems like every bike has at least a couple of attachments that are 'buggered up' somehow. And this one needs a paint job for sure. I will wait on that till I test ride the new motor/tranny for a while...

I am really looking forward to getting this bike on the track and onto some of my favorite canyon twisty roads, with a fully functional tranny..Even with the 'weak' second gear, shifting past it and lugging out of corners in 3rd, I've been able to pretty much keep up with my R-1 and Daytona 675 buddies...I like the handling of the F4i, for sure. Very confidence inspiring...fork legs set up about 5mm and pre-load full hard, for now.

Some stiffer fork springs and a nice paint job will make this bike for me, with a fairly low investment cost overall....cept for tires, which seem to only last me a month....

I am tempted to start looking for a 954, too. Why, you say? Cause.....
Don Hanson

 

Got the bike dangling from my shop rafters on a come-a-long. Rear wheel and swing arm off, everything un-plugged, motor mounts loose and replacement engine ready to go in....Should have it back together tomorrow if I hit no snags...What are the odds that I'll be done with no mistakes requiring backing up on the swap? LOL.

I know myself. Probably get everything back on and go....."Did I remember to re-attach that throttle cable at the TBs?" "Did I actually tighten that top shock mount after I shimmed it for increased rear ride height???" Something...

Don Hanson

 

Good luck man. Early next year I'll be keeping an eye open and probably doing the same thing once I get my tax return. I can live with second gear popping out for now, but it's an annoyance I definitely want to get it fixed.

 

Where are the pics??? ;-)

 

It is in and running. Sounds good, seems to function, though I have yet to get a test ride. Here are a couple of things that had me head scratching for a little during the final stages.

I 'forgot' to install my chain with the swing arm. Getting the swing arm on and adjusted is pretty tedious, entailing re-torquing everything in sequence, so I elected to break my chain rather than take everything apart again...

The starter won't operate without the 'level sensor' or whatever Honda calls that part that is in the front fairing....I went back through a lot of wiring and relays checking, before I got round to hanging the front cowl on and plugging in the harness to that sensor to try that....

Next, I missed one plug...left side by the frame..Took me a long while to find that one, then the bike fired right up....smoked a bit, probably from having the motor on it's side during transport, etc...but it cleaned right up...and I found the idle adjustment screw....

The fairing pieces took me a couple of hours...because like every Honda I've ever owned they were all buggered up and broken here and there with many 'hardware store' substitutions and poor fitting issues.

While I had the motor out I shimmed the top rear shock mount about 3-4mm to add some ride height back there. The springs on this F4i are too soft, I have both ends almost maxed out . I still can't get the sag I want and I'm only about 175lbs.

All in all, the swap over wasn't too difficult, though it took me a long time...probably about 12hrs...due to being unfamiliar with the bike and having to work around not having all the proper shop tools...

Don Hanson

No pics...there are plenty of those engine-swaps elsewhere and this 'blacked-out' bike's looks are ugly right now so I am not anxious to show it off.....

 

your rear shock should be alright, and considering rear shocks cost 1,500 bucks thats a good thing, the front shocks probably can use new springs, and a good possibility new rebound valves depending what springs you get. now that i think about it the gas may be shot in the rear shock, and i've yet to see if they are rebuildable.

 

I got my first ride since the motor tranny swap. What an improvement! This trans is very smooth...about the smoothest Honda shifting I've seen...and it is a totally different bike with smooth shifting and a full range of gears rather than working around having no real second.

The motor seems quite strong and smooth. It does pop frequently on drop-throttle at high rpms....Not sure what that is. Adding a 4mm shim at the top of my rear shock makes for better turn in ...could be a new rear Q2 that I mounted, too.

I still have my intermittent 'no start' issue....This is weird. Sometimes after about 50-100 sporty miles the bike had a 'dead battery' when I try to start it.
The lights come on and everything but when I touch the switch....everything blanks out, sometimes after a couple of half-hearted rotations of the motor. I can push start it and ride for a mile or two....starts right up again with the button. I rode home about 10 miles today after a 'no start' episode and tested the battery voltage...it was at 12.77v, about 80%... When I test the voltage output at the battery, I see good charging. This is exactly the same symptoms I saw with my old motor...I now have a different stator, starter, and I think maybe the switches too...I forget... Just doesn't make sense to me..anybody want to guess?

I will post this on General Tech, too

Don Hanson

 

Try load testing the battery, mine had the same problem. Battery reads good voltage but it was bad