Overheating a VFR400

[Rayray401]

Ok, basically i think i overheated my VFR400 cos i didnt have any coolant left in it. Just wondering, what are the symtoms? and basically now the bike starts to feel sluggish and lose power and then stall after riding for a while..and also there seems to be a klinking sound on the upper left of the engine, could someone pleassseee help ><

[avgas]

yep - basically bakes itself. you lose power as the engine gets hotter - may eventually stop.
Thankfully if you let it cool down, put something in as a coolant you may be able to get it home......at which point it requires a strip down

[James Deuce]

Ok, basically i think i overheated my VFR400 cos i didnt have any coolant left in it. Just wondering, what are the symtoms? and basically now the bike starts to feel sluggish and lose power and then stall after riding for a while..and also there seems to be a klinking sound on the upper left of the engine, could someone pleassseee help ><

It's fucked. Open your wallet and let the money fly out.

[CookMySock]

Let it cool down completely (3-4 hours or better - the next day - you have a clear head then.) With no coolant in it, choke and see if it will kick over and start - if it does then STOP it immeditely, and fill the cooling system with plain water and put the cap on. If it wont start, then quite likely its lost all its compression and will never go without a complete rebuild. You might try pushing it for a bit, but STOP IT when it AS SOON AS it starts and get some coolant in it.

Check it everywhere for leaks, and try start it again. If it won't turn over, then coolant is getting into the cylinders, and you are screwed. This is why we tested it quickly first.

If it will start then run it for about 2 minutes (you did put water in it didn't you?) and then turn it off, and recheck the coolant level. Put the cap on again, and start it and then let it warm up at about 2,000rpm, until normal operating temperature and see if the fans kick in. Watch carefully for leaks at this point, because there will be a good reason why it dumped all ite coolant (cracked hose, stuffed pump seal, etc.)

Listen for funny noises and any rough running, like one cylinder not firing. You can test by removing one spark plug lead at a time while the engine is running. If pulling the lead off makes no difference, then that cylinder is not firing.

If it sounds good, then ride it very quietly down the street and back and WATCH THE TEMPERATURE GUAGE - it should stay as normal. If the temp starts to climb over normal then head back home very gently and idle the engine and see if it continues to climb - if it does, then turn it off and leave to cool completely (cold engine) and refill the radiator again, and check for leaks. A repeat the warm up and drive down the street again.

Don't take it on the motorway, or piss off across town on it! Up and down the street only, until you are satisfied it is ok. And remember, there is a good reason why that coolant spat out on the ground, so you need to find that.

If you are really really really fucking lucky, you might have got away with it, but usually you don't. Sorry.

Steve

[racefactory]

i should add the bike sounds good, good power, no unusual behaviour until it has been run for a good while....

oh and why there wasnt any coolant is a long story, the focus is the problem with it now that it has overheated.

[Rayray401]

so...is it overheated but probably still fixable(dont need a new engine)? or did i burn the toast(fully fucked inside)?

[Rayray401]

ok, the klinking sounds like pistons going up and down except its hitting something on the way, so hope someone can explain that..its quite subtle when the bikes cool..but when the bike gets hotter it gets abit louder

[CookMySock]

Gee you might have got away with it. Sounds like a valve clearance is a mile out and one is clipping a piston top. Get your valve clearances checked.

Steve

[Rayray401]

hmmm thats good news to me XD..but the bike still loses power after a 10 min ride?

[James Deuce]

Dude, it needs a tear town. Until the engine is dismantled, you won't know what you've done to it. There are two kinds of NC21/NC24/NC30/NC35 owner.

1. Fastidious. Convinced 400cc Honda V-Fours are the Ferrari Dino of the bike world. On a twisty road they casually ride around the outside of Ducati 1098s, and Honda Fireblades without getting out of the seat.

2. Thoughtless ham fisted amateurs who paint them purple with a spray bomb and aren't aware of a "service schedule". Invariably describe Hondas as "shit" when the engine finally seizes solid after 20 years of serial abuse. Oh, and no oil or coolant.

It is likely that metal has met metal and that means a substantial engineering project to get it back to a running state. I'd be looking for a good second hand engine from a wreckers, but them I'm cheap and always look for the easier option.

It's impossible to diagnose engine damage on a web site. Trailer it to a bike shop and get them to to have a look. Bear in mind they won't do that for free so you may want to consider the concept of "throwing good money after bad" before you hit the shop.

If I were you, I'd stop running the friggin' thing, at least until you've had the engine pulled to bits and the damage surveyed. You're just doing more damage that you'll have to use your wallet to fix.

On second thoughts, sell the bike to a wrecker and buy something else. It'll be cheaper in the long run.