Over heated at 131mph

Hi Guys and of course Galls, Love this site, it saved me buying 150 euro plus worth of a new clutch by fixing the problem with a sewing needle.

This is my first post.

I got my 1993 VFR 750 FP about 6 months ago. It was in a right state and I have been repairing it ever since. I have it on the road 3 months now and most problems have been solved. I owned a cg 125 for my first bike and a BROS for my second. I had tried top speed on my first two bikes considering it only natural and tried with my VFR.

I need a new air filter, which I have now, i got a K and N reusable, just waiting on the oil before I install it and i think thats why the top speed was a little low.

Heres the problem

I got to 210kph and held it there for a good spell. The engine cut out and I pulled over. THe bike would not start. Then I tried the choke and found that the bike would stay running with revs above 4000 or 5000 rpm then cut out when I let off the throttle to idle. To cut a long story a little shorter I had a cup of tea and a ciggy and tried the bike an hour later out of curiosity and it started and idled and was just fine.
That was a month ago and the bike has been fine since but I have not gone much over 160kph since in case of more trouble. I have been told its most likley electrical.

Has anyone had this problem or know the exact or probable cause?

Kevin

 

Could be electrical. Have you checked your charging system? I would start there by seeing how many volts you are putting out. When you were doing this high speed run how high was your rpm? And for how long? Could it have starved itself of fuel? Having your floats set wrong could cause that. Have the carbs been cleaned recently along with your petcock or any fuel filters? Does your bike have a fuel pump? If so you may want to check it as well. Good luck

 

I would start by inspecting plugs (stator to regulator-yellow 3 wires) (Regulator plug 5 wire/3 yellows-red and green wire) Plug that goes to starter solenoid (next to battery.) If you can get it to run, check voltage at battery while idling and then reving up to 5000 rpm, you should get over 13.7 to 16 dc volts.

Pull plugs, check condition. I would pull the carburetor assembly as an entire unit (never seperate them from the plate!) Go thru them. Just the basic stuff really. Check coolant, etc...The electrical stuff mentioned above are easy look-and-sees. AnywhoooOOOOo we want pictures

You get me? pictures of naked hooters and bikes :vtr2: Cheers.

 

Thanks both of you guys, Im really dumb right because I forgot to mention that i got a new regulator the other day. The old one was overcharging the battery. Now all volt mesurements are correct, I very trusted mechanic checked it out when he replaced the old one. That could have been the problem I asked about. The reason I didnt mention it is i never connected the two. I replaced the regulator because I had it checked when the main lights got twitchy. I would get a split second of darkenss when I switched from dims to main light. That turned out to be the regulator being faulty.

I dont know if I have solved the high speed overheating but it does make sense that I may have. If I rush out and test it now though I may blow my new regulator so I will not rush out now but test it in due time when I have money for a new one. What do you guys reckon? Problem most likely solved?

Kevin

 

Stalling ?? check fuel flow quantity in line from tank leading to the fuel pump for a possible clogged filter, kinks in the line.

For overheating, flush out and replace the coolant if it's more than 2 or 3 years old, then replace the radiator cap with a new one.

It's a small place there, so i wonder where anyone could find a road to go that fast, eh ??

 

Re the problem, I have not replaced the coolant, because its at a good level and I had lots of other stuff to do, I will though,
Its not stalling, it just was when it was overheated, so I dont think ill follow the other idea for now.

Re the roads in ireland. Its a small county but there are lots of places to go that speed and faster. I live in waterford,if you find a map online waterford is in the south east, near the coast. I have plenty of opportunity to do that speed and faster on a road between waterford and dungarvan which is 30 miles away. That not even a good road, there is a main road to the capital Dublin where you can get up to serious speed. I know a guy who did 220 on that road on a hyabusa. Now there are alot of bad roads here, but the main roads, of which there are a few in my area, are good enough to do some serious speed. There are areas of Ireland, the rural areas where a biker might need to travel a bit to find good enough roads. I bought my bike in mayo and the main roads up there are bad, but lucky for me I dont live there. I lived in cork and there are roads there good for serious spees but the traffic is heavy most of the time so I guess im lucky really to have good roads and bad roads which can also be alot of fun provided the surface is ok. Some small village roads have really bad surfaces and potholes that could be fatal. If im on these roads i take it very handy until I know the road. I must say though that im not a speed demon although I like to ride my bike and trying out top speed to me, is just a part of that. I dont always push to the limit. I found out on a long journey once that pushing to the limit is ok every now and again but on a long journey, ie a days riding, I should take it steady.

 

Good info, thanks. You got a relative or mate in the constabulary ?? Ova' 'ere, in most states, you'd spend a few hours in gaol and pay a ginormous fine, loose your license if cought anywhere near that speed.

 

Well its like this lad, the law is that if your caught doing over 75 on those roads its penalty points, so many and your off the road, they reduce points after so many years. A mechanic told me recently that if your caught doing over 100mph then your banned for a few years.

Truth is though, before i even got a bike i talked with some bikers, randomly and differant guys and it seems the gardai ( Irish Police/ constabulary is UK) dont pay as much attention to bikers as they do cars. Bikes dont have registration on the front and the speed cameras cant pic up a reg as they face trafic, not scan after it has passed. I think some gardai are lenient with bikers because they can moslty only damage themsleves if they crash. This is not aways true as you know a bike can kill someone. Moslty though the driver is the one who gets hurt where as a car can do serious damage to other vehicles.

I keep to the speed limit unless its a good sunny day and I feel like a blast, these sunnt days are few and far between in Ireland.

PS, now i have admitted all this I am never posting a pic of my bike on here for the saftey of my license.

 

Yeah that's it just false bravado. And I always do the speed limit here in Florence Alabama. Wouldn't dream ofdoing any wheelie either.

 

Yes true, Im just paranoid. Dont mean to pass it on.

I had a trip today on a good road to pick up K&N cleaner and oil for my new(second hand) K&N air filter. I took the bike up to 200kph but I didnt stay there long so I have not really tested if the regualtor fixed the overheating problem. I did talk with a guy today who said that the regulator was almost definatly the problem.

On a legal note, I just made up that I did that speed for the craic!!!!!

 

I'm still wondering how any electrical problem suggested above could cause overheating at speed ???????

 

Here it is right, when the engine concked out two bikers stopped, then another. From the symptons, ie the bike would not start, ( I cant recall now exactly how it sounded, I only thought to post this two months after it happened) it would start with the choke down and only revving after 4000 or 5000, the guys suggested and were almost certain it was electrical although no one could say what, they were all fairly certain it was electrical.
Since then I only put 2 and 2 together when i reoplaced the regulator. Now maybe I got 5 and the problem is still there. Can you tell me anything on the matter?

I have not really tested to see if the problem is still there and to be honest I dont really feel like putting the bihe through it unless I know its fixed so any info on it would be greatly appreciated.

I have yet to change the antifreeze since I got the bike. Thats something I may do tommorrow as I have a new front brake lever to put on and may do both same evening. Does the antifreeze/coolant go off and can this drastically reduce the cooling systems capabilties.

Answers to either question would help out, although im going to do the antifreze anyway as its already been suggested and its a 15 euro fix so it cant hurt.

Later fellow VFR riders.

One last thing. The K&N air filter I put on the bike today has made her sound better, given a healthier power output (if that makes sense, it just feels like im putting less pressure on the engine) and ill bet fuel economy, hard to test for me, has improved as K&N said.

Goodnight from ireland.

 

Seems more like it would be fuel related than heat related (lots of air to cool things off at those speeds, and lots of coolant flow at those rpms). I'm guessing you were close to WOT for that time, and up at like 9-10K rpm, which is going to take a lot of fuel, and so the fuel pump would need to be flowing full-bore to keep the carbs full at the right level.

The difficulty restarting sounds sorta like the bowl ran low, and then you needed to turn it over for a while to get them to refill. Using the choke would compensate for low levels in the bowls. search for problem on starting the engine when hot (vapor locked lines, etc).

 

I wasn't going that fast officer but the trees were passing me at over 100 miles an hour...

post up pictures with your registration covered with a shop rag.... no excuse to not post them .....were have few rules here and pictures are one of them....

 

"have yet to change the antifreeze since I got the bike. Does the antifreeze/coolant go off and can this drastically reduce the cooling systems capabilties...."

YES it does go off after a few years like a blancmange left out in the Irish rain. Change the rad cap too cuz if the spring weakens or the rubber gasket cracks, it won't hold pressure proppa-like and cause over-heating.

 

Hi all,

Thanks for the info, I think the fuel pump could need replacing. Im going online to see what the bowls are. Info on the cap for the coolant is good because I have the antifreeze bought.

I will post pics as soon as I take some, right now I dont have a camera, honest. Im a student and cant just pop out and buy one either.

K

 

I dont think its the cooling system because when I drive normally the temp gauge only goes half way up when its hot and I go for a blast, its winter here in ireland now, temp around 10 c most of the time. Im going to change the coolant anyway.
What im going to do is buy the fuel pump repair kit from wemoto and that combined with my new regulator and of course the coolant which I dont think will solve anything on its own, should fix it.
I have a suspicion Im driving on three cylinders and its been like that since I bought it.
It was a wreck when i bought it. I have been hard at work restoring it. New plugs.... Im back in college and so I dont have alot of time at the minute, I would have done more work this weekend, but I dont see any free time until the end of the month.

Any advice on how to pop a wheelie? Saftley...

K

 

:vtr2: dont do wheelies unless your on der race-track pulling away from the wave of der flag :smile:

 

Thats soooo true, now does anyone want to give me advice on how to wheely? Its supposed to be easy enouhg on my vfr compared to some other bikes.