VTR250 not getting up to speed?

**otter** · 6th August 2011, 02:09

Hi all,
First post here

So, I have a 1998 Honda VTR250. Done almost 37000KMs.

I've discovered two things,
1) I can get to about 140KM/Hr in 4th gear (correct, about where the red line should be (no tachometer)), then when I change into 5th gear, I lose power and my bike will only hold at about 130KM/Hr, even with the throttle screwed right around. From other VTR250 owners reports I should be getting 155KM/Hr out of it in 5th gear (I'm not very heavy either).
2) If I ride for more than a few minutes with the throttle screwed right around, I also start to lose power and can't hold more than about 110KM/Hr (In 5th), I'm pretty sure I lose power and this happens regardless of the gear I'm in. It's as if my carbs don't fill up as fast as I'm emptying them or something? I can then ease of the throttle for a couple of minutes and the power will come back next time I open it up.

I'm a bit stumped as to what could be causing this (unsure if related).

Any help will be appreciated this much *spreads arms wide*! I've got a ex250 and gt250r to keep up with on the motorways :/

**gammaguy** · 6th August 2011, 03:50

fuel.

its not getting enough

**JimO** · 6th August 2011, 08:18

you do realise that your going to die in a huge fireball if you go over 100ks

**otter** · 6th August 2011, 11:09

Originally Posted by gammaguy

fuel.

its not getting enough

Any ideas on getting more?
Any way if I can test if it's a problem before the carb or after the carb?
I guess I'll go nuts with carb cleaner tomorrow when I put more her apart again.

Originally Posted by JimO

you do realise that your going to die in a huge fireball if you go over 100ks

Don't worry...I'm not in a hurry to do that again...

**ducatilover** · 6th August 2011, 11:27

Pull the spark plugs out and check them against this handy page http://www.angelfire.com/fl4/pontiac...Readplugs.html

How clean is the air filter?
Have you had the valve clearances done?
Have the carbs cleaned, balanced and your fuel tap checked.
It's worth replacing the vacuum line to the fuel tap too, if it's damaged you will get restricted flow.
Replace the fuel filter.

**otter** · 6th August 2011, 11:51

Originally Posted by ducatilover

Pull the spark plugs out and check them against this handy page http://www.angelfire.com/fl4/pontiac...Readplugs.html

How clean is the air filter?
Have you had the valve clearances done?
Have the carbs cleaned, balanced and your fuel tap checked.
It's worth replacing the vacuum line to the fuel tap too, if it's damaged you will get restricted flow.
Replace the fuel filter.

OK, I'll check my plugs tomorrow.
I'm not sure what a dirty air filter looks like, but when I checked last weekend there was still plenty of cleaner looking surface with a few dirty patches.
I checked the balance of the carbs last week with a tube with fluid in it. How would you check the fuel tap?
I'll clean out the carbs and do valve clearances tomorrow. And get me some more tubes and a fuel filter next available day.

**ducatilover** · 6th August 2011, 11:57

If in doubt just replace the airfilter, it's not expensive and the bike will love you for it.

With the fuel tap, I used to put the fuel line to the carbs in a bowl/clean bucket and then suck on the vacuum line to see if it was holding vacuum. Mine had destroyed the O-ring in the tap, sadly Honda tells me they only sell the tap and not the seals/o-rings.

**otter** · 6th August 2011, 12:02

Awesome, thanks. I'll try that

**otter** · 7th August 2011, 11:02

OK, last night I:
Checked the fuel tap, when I sucked on the vacuum tube there seemed to be a good constant flow of fuel.
I think I cleaned the carbs out properly, they're a bit more complex that the last carb that I cleaned.
I showed Dad my air filter and he says it looks pretty dirty, so I guess a new one is in order. I'll get the new vacuum tube and fuel filter while I'm at it, Do you have any idea where the fuel filter is though, I didn't see anything on the line.

I'm up to doing the valve clearances, my manual says that I need the special tool "camshaft lifter", do I really need one of them, it also says that I need a special 8x9mm wrench and a valve adjust wrench but I'm not up to actually adjusting them yet?

EDIT: Also, I haven't looked at the plugs yet, but what fuel should I be running my bike on?

**FJRider** · 7th August 2011, 11:17

There is usually a filter attached to the fuel tap INSIDE the tank. A lot of shit gathers at the bottom of the tank ... especially older bikes ...

Unscrew the tap off the tank (best to take the tank off first) and flush the tank out. If the inside of the tank is badly corroded ... it may (should) be lined ... It will then stop a few issues with fuel later ..

**ducatilover** · 7th August 2011, 11:22

The tools for clearances = 8mm ring end spanner and a flat blade screwdriver and feeler gauges.

I ran the best fuel in my VT250, but, it probably doesn't matter too much.

The filter is where FJrider said.