I've finally run a tank through my
little V4, and was a
lot disappointed. Anyway, here it is. This is the only picture I have of it.
Right now it has the seat on it(of course), but the rear side panels are still off for now since they aren't doing a great job of staying on. It also has the front fender on it, which has little fork deflectors for the first few inches.
This was the first bike that the new trailer I convinced my dad to buy(instead of renting the u-haul barn door, thread in success stories) hauled home. We bought it for $2000 CAN not running, but looking great. Turns out the kill switch had failed. It had sat for long enough that the gas in the carbs turned green. Tons of bolts were loose, clamps were missing, coolant looked rusty. Whoever was working on this bike had no idea what they were doing. Thankfully me and my dad rescued it.
I rode it for less than 100 km with the stock gearing, 15T/45T, which put it at 5000 RPM at around 48 mph. I decided that was ridiculous so I dropped down FIVE teeth in the rear sprocket and have a 40T on there now. It should be noted that the "bolt pattern" so to speak is different between the NC21(my VFR) and the NC30(newer, dad's vfr), so you can't just buy sprockets from an NC30 or NC35 and slap them on there. Thankfully, JT sprockets has a well filled out catalogue that even had sprockets for my rare bike. The new sprocket puts it at around 4400(?) RPM at the same speed. I still feel like I can go taller, first gear isn't even as tall as the NC30's yet. I can go as tall as a 36T rear sprocket, so when the chain and sprockets wear out, that's probably what i'm going to get. On the highway, I am just under 6000 RPM at 110 kmh(new gearing), while my dad's NC30 should be at almost 6800 RPM for the same speed.
Here is the new sprocket overlaying the old sprocket.
While I was in there, I swapped over the sprocket's rubber dampers to the CORRECT ones. Seriously, who put this thing together??? The drivetrain lash(more like
CANYON) was just stupid with those little dampers. The larger dampers are the correct size.
So about a third of this tank was with the stock gearing, the rest with the new taller gearing. All of this tank was done without the rear side panels, which may have hurt the mileage a little. I ended up going 101.2 miles with 2.084 gallons, getting 48.5 MPG. To compare, my dad's NC30 went on the same trip with me(excepting the first 1/3) and got 54.6 MPG. I told him when we filled up that he better not have gotten higher MPG than me, that's not allowed. He thought that was funny, cause I was trying so hard(for 2/3 of this tank, anyway), I was tucking at higher speeds, shutting off the engine at stops, short shifting, coasting for stops, P&G'ing, and I had taller gearing. And he STILL got better mileage than me.
So, what I think caused the bad mileage is the fact that I was pushing my little brother on his bicycle(while straight piped....), and I did a good amount of hard acceleration this tank. My bike is also running brand new bias ply tires, so that can't be helping the mileage either. Hoping for AT LEAST 55 MPG next tank.
Currently, the bike has a deadzone between 5500-6500 RPM, and the choke barely works, so I have some things to figure out.
In 60-65 degree weather with my riding style, the temperature gauge was only sitting around 1/3 the way up, so I MAY have a stuck open thermostat. When I got home, I measured some temperatures. The oil filter(in close proximity to the headers) was 145F, the oil cooler was 125F, engine cases were around 150F. I should block the oil cooler with temperatures like that.