Need help choosing and need a little advice

What's up guys!

So I picked up a 2002 VFR800 a few months ago...

The bike has 29k miles on it and absolutely nothing done... (other than me removing the giant heavy arse factory exhaust, and installing a "turn down")

I'm having a few issues with it and Have been going nuts researching stuff. (can't tell you how many nights I've had 10+ web pages up comparing peoples opinions)

SO...

* It gets horrible MPGs (It never gets passed 135-145 degrees while riding) I'm almost positive the stuck open thermostat is to blame for my crappy mpgs/performance)

* It stutters a little below 3k rpm. (I'm thinking maybe spark plugs or regular tune up stuff) (Maybe I'm just used to my old 05 R1? I could get it to 30-40mph in 1st, and then go straight to 6th and cruise...)

*It will not keep a battery charged. I can recharge a battery and it drives perfectly fine... Matter of fact, the best example that I can give you is I was hanging out with some car buddies after a meet, It was like 42-45 degrees that night and I was aware of the bikes issues to get hot, so I let it sit and idle for around 30 minutes.... This was also my test to see if the fans would kick on / if it could maintain a temp. The fans came on, she stayed around 200 and purred like a kitten.... HOWEVER... My newbie self stalled it, and the battery was so dang dead that I couldn't even get a CLICK from the starter. So a few buddies push started me and I rode home... It was a 12 mile ride and it went perfect.. no issues... I cut the bike off at like 55mph, tried to start it and it still wouldn't turn over, so I let the clutch back out and kept on my ride... The battery read out completely gone (OH BTW- Brand new battery) I re charged it and all was well...

That's my biggest issue... So I've read that these bikes have HORRIBLE R/R issues... (How do I always manage to buy shit that can't keep a battery charged?! *2003 cobra, multiple LS1 powered vehicles, 2g DSMs.. haha*)

Anyways, I'm down to fix this issue... but there are a few options and I'm pretty confused on what I'm ordering and what's the best option...

There's
Wiremybike.com kit... Seems like it's a MOSFET R/R from yamaha but you still have to buy their VFRharness

Roadstercycle.com kit... I'm really unsure which to get with this... I guess we're the 3 wire system? The Super Mosfet Kit FH020AA?

I'm reading a lot of good about the roadster kit. /// Also reading that Ricks motorsport electrics is a good option, but it isn't actually a yamaha R/R...

Basically I'm starting this thread in hopes of having a few questions answered / verified.


On a sidenote while I'm here...

I'm considering a +2 rear sprocket, KN filter, a header, and PCIII.... With said mods, will the bike actually pick up some power?

AND last but not least... I have to tear this thing apart to change the thermostat... Thanks honda for the excellent location of the Tstat... Is there anything I need to check /// you guys recommend replacing while I've got everything torn apart?


Thanks for your time gents!

 

Only thing I can mention from my experience is that I know my VTEC valves on my 06 wont' actually kick in until the temp hits 150 degrees, so if you're regularly hitting over 7000 rpms, and the vtec valves aren't kicking in that could be the cause of your gas mileage woes. My bike also stutters a bit more at lower rpms until she's properly warmed up too. It also feels as if it's stuttering if I'm running 2500 rpm or lower in most gears. As to the electrical stuff, I'll let someone a little more experienced chime in there.

 

Yeah, it won't operate VTEC under 150. I figure that out too... Now I will say, one time I let it sir and get to 185 degrees, raced a buddy of mine with a 07 Ducati 848 and not only could he not get away from me, but my big ole girl came off the ground

 

She'll do that from time to time. VFR's are heavy machinery, but if the conditions are right, the front end will definitely lift up.

 

I installed a MOFFET R/R from wiremybike & have ZERO issues since then. The VFRness is a great option but NOT required. You need to do the entire "DRILL" to verify what problems actually exist with your electrical system before just replacing parts willy nilly.

I wouldn't bother with a power commander. Everyone I know who has installed one has gotten worse gas mileage for a very minor increase in power and some better tractability in the lower RPMs.

Forget the K&N air filter, it's a waste of money & will only let more dirt in the engine. Stick with the OEM paper filter.

Changing the sprocket is the single easiest thing you can do to get better acceleration. It's at a price as your speedo will be off, top speed reduced, & fuel economy will go down.

If you're looking for more power, perhaps you have the wrong bike....

 

I've seen them put around 110whp down and around 70ftlbs of TQ with the mods I spoke of. I'd be getting the bike dyno tuned. Honestly, I very much enjoy the bike... but by your logic, Modifying my 2008 Saab 97x Aero (trailblazer SS in a saab suit) would be a waste of time. Especially when I have the lightest C5 corvette that has seen quite a few mods under my ownership...

My point is I 100% love this bike. I've already stripped it of all of it's touring fatty suit weight. Don't get me wrong, she's still heavy- and I know mods aren't bountiful for these machines, but My god does that V4 make me feel like I'm riding a machine built to break the speed of light. haha, Like everything else I own, I want more from it than the restricted companies could release them at.

SIDENOTE: KN filters have ALWAYS out performed a paper filter. I've put over 60k miles on a 4G63 and another probably 75k on an LS1, Both I've been in to, both had KN filters the entire time, both showed zero evidence of particulate damage.

I do appreciate your answer though. How simple was the install of the wiremybike kit? I assume you did the VFRness too?

 

You can't compare a car filter to a motorcycle filter, they aren't working the same. I have a K+N filter on my car,. it may add a little of power, but you have to clean it all the time for it to work. It would seem the OEM filter on a vfr keeps the most dust out and holds the most dirt out of the engine. The OEM filter doesn't rob much power either. The only filter I think might out perform the stock filter might be the pipercross-they cost about $90. Another factor is changing the air/fuel ratio using the stock map-its going to go a bit too lean with a High Flow filter. I all ready hear a few pops with the 2 bos slip-on carbon, so a aftermarket filter might actually make the bike lose power.:smokin::horn::whoops:

 

Your thermostat must be stuck.
I disagree about the Power commander, I put one on and ran a map from Dyno jet and the bike smoothed out in low rpm's, vtec transition was smoother , mid range is a little bit better, top end can't tell. Overall drivability is much better. Gas mileage may have dropped a tiny bit but hard to tell as I think I'm twisting the throttle a bit more.

 

lolwut? I do believe a filter works as it's named... It filters.... Now before I make an ass of myself and get no help I'll stop... but in all seriousness- car, truck, motorcycle, ATV, lawnmower... an airfilter is an airfilter.

 

Check the fuel pressure regulator vacuum line, unplug it while it runs to see if any traces of gas comes out. Mine was doing basically what you're describing (including the horrible gas mileage and temps that wont rise) and it all went away after i replaced the bad FPR which was leaking internally and flooding my motor with gas.

 

simple as unplugging the old & plugging in the new. Piece of cake.

I haven't done the VFRNESS yet, but plan to. A direct connection to the battery can only help~

I didn't have the heat problems so many have with connectors and wiring. All my connectors look like new.

 

FYI: I've not seen a single VFR that was happy below 3000 rpm. The only time I go below that is in 1st or 2nd gear at light throttle.

I recently rode a friend's 2007 & to me it wasn't happy below VTECH engagement. I much prefer my 5th gen gear driven valves~