Had the bike down the local dyno shop last week just to get things checked out after some earlier playing. Turns out I used to go to school with the bloke who runs the place. Anyway He said I had done a good job so far, gave me a bucket load of free advice and sent me on my way all for the princly sum of 30 quid.
One of the little gems he gave me was to lift my needles one more click as he was sure there was still a little more left in the old girl.
Jobs done now and after a good spin on the weekend it certainly pulls much better. Only problem is, when driving in slowtraffic at about 2.5k rpm the engine seems to hunt. Ive pulled the plugs and the rear is spot on but the front looks as though I'm running on choke. It's as sooty as a miners crotch.
I,m pretty certain both neddles have been set to the same setting(I,ve done it enough times in the past )Has anyone had any sticking carbslides or choke plungers or is there something else I can be checking as I can,t see anything obviously wrong?
Pete.l
Carb problem
Pete
This is so spooky,
Went to have a dynojet fitted last week & on the way there the bike started missing like a pig & down on power actually thought i,d burnt a valve,(always the pesimissed
)anyway trundled to REPs in caldicot (very good 
) & bike seemed to clear itself.
Fitted dyno mentioned about problem but everything seemed tickety boo on the dyno,checked plugs seemed fine,
on the way back home it started again but not as bad,So decided to put new plugs in. went out for a ride today to see any different & much better but there is now a hunt under 3000rpm & a slight glich on take off so im off to the dyno again to try & smooth it out.
Are you running with the snorkel on or off the air box,mine is off & makes a big difference apparently
Dom
This is so spooky,
Went to have a dynojet fitted last week & on the way there the bike started missing like a pig & down on power actually thought i,d burnt a valve,(always the pesimissed
)anyway trundled to REPs in caldicot (very good ) & bike seemed to clear itself.Fitted dyno mentioned about problem but everything seemed tickety boo on the dyno,checked plugs seemed fine,
on the way back home it started again but not as bad,So decided to put new plugs in. went out for a ride today to see any different & much better but there is now a hunt under 3000rpm & a slight glich on take off so im off to the dyno again to try & smooth it out.
Are you running with the snorkel on or off the air box,mine is off & makes a big difference apparently
Dom
definately check the choke plungers as the cable can come out of it's seat and stay open, also check the route has no tight spots. A good way to check it to loosed the knob on the choke handle and pull it and check it springs back in easily, also listen for the choke needles seating.
black plug means jetting is way out so defo check the choke.
Del.
black plug means jetting is way out so defo check the choke.
Del.
-
Pete.L
- Forum Health And Safety Officer
- Posts: 7224
- Joined: Fri Sep 26, 2003 5:09 pm
- Location: Bristol
Thanks Guys,
Ever think you should have just stayed in bed some days?
Started a slow dissasembly last night,checking each bit in turn. As soon as i lifted the carbs out the problem was quite apparent. The front choke cable had been dislodged. Must have been too heavey handed when shoving it between the expansion bottle and water pipes
. Any way thought I had better check the needles to make sure they where seated correctly whilst I was there.
Everything checked out so I slung it back together (
hate the front breather pipe on the airbox by the way )Pressed the starter button and hey presto she comes to life Give her a rev and nothing. . Some silly b-sterd forgot to connect the throttle cables 
So, Tank off. lets start again.
Finally everthings back together again and everything is working as it should. Time for a beer
Boon Said
Bang on with the info Del.
Just goes to show. Incompatance Rules The Day :oops:I should have stayed in bed 
Pete.l
Ever think you should have just stayed in bed some days?
Started a slow dissasembly last night,checking each bit in turn. As soon as i lifted the carbs out the problem was quite apparent. The front choke cable had been dislodged. Must have been too heavey handed when shoving it between the expansion bottle and water pipes
. Any way thought I had better check the needles to make sure they where seated correctly whilst I was there.Everything checked out so I slung it back together (
hate the front breather pipe on the airbox by the way )Pressed the starter button and hey presto she comes to life Give her a rev and nothing. . Some silly b-sterd forgot to connect the throttle cables So, Tank off. lets start again.
Finally everthings back together again and everything is working as it should. Time for a beer
Boon Said
Sorry Boon I,ve no experiance of this. Mine is on. I Have read a write up some time ago when one chap was trying to tune his air box by putting loads of large holes in it and seeing what the affects were on a dyno. He concluded Honda had made a good job on the airbox and ended up replacing the now cheese grater looking coverAre you running with the snorkel on or off the air box,mine is off & makes a big difference apparently
Bang on with the info Del.
Just goes to show.
Incompatance Rules The Day :oops:I should have stayed in bed Pete.l
Re: Carb problem
Many months ago when I was reading up on vtr's before I got mine, I read on a web site (the name of which I've forgotton) that lifting the carb needles one notch improved the fuel economy and range. Do you think theres any truth in this, and if there is, would it only work on bikes that have been modified, i.e race pipes etc, or standard bikes as well (like mine).Pete.L wrote: One of the little gems he gave me was to lift my needles one more click as he was sure there was still a little more left in the old girl.
Jobs done now and after a good spin on the weekend it certainly pulls much better.
Pete.l
I've always meant to ask someone this and now i'm getting my chance.
Rich.
-
Pete.L
- Forum Health And Safety Officer
- Posts: 7224
- Joined: Fri Sep 26, 2003 5:09 pm
- Location: Bristol
Nah!
Lifting the needles or putting washers under std storms is going to allow more fuel into the engine.
When I first had mine if I was really light on the throttle on a good run I could get 46-48 to the gallon. After a little tinkering (still with std pipes) I was down to 42.
But Responce was up
so Who cares.
Pete.l
Lifting the needles or putting washers under std storms is going to allow more fuel into the engine.
When I first had mine if I was really light on the throttle on a good run I could get 46-48 to the gallon. After a little tinkering (still with std pipes) I was down to 42.
But Responce was up
so Who cares.Pete.l
I must be getting better at this internet thing, I found the web site. http://www.roadracers.co.uk/vtr.htm I was almost right, it was jets that needed changed, not the needles. So, what would be the effect of changing the jets to 170F and 175R? Would it give you 15 miles per tank as this guy claims?
Rich.
-
Pete.L
- Forum Health And Safety Officer
- Posts: 7224
- Joined: Fri Sep 26, 2003 5:09 pm
- Location: Bristol
Hmm. Interesting!
Most people when looking for more power try larger jets and increasing the flow of fuel through the combustion chamber. What he says in the beginning makes sence. Put smaller jets in and lower the needles by removing the shims and it will give you better fuel economy. But run the bugger too lean and it will be very economical right up to the point it burns your exhaust valves out or holes your pistons or both.
Dyno jet actually reccomend 170 mains on a std exhaust front and rear but they also claim thier jets flow differently than std main jets.
He later goes on to say he has had the head gas flowed and is running a race exhuast system. This would require bigger jets as the flow has been increase to keep the air/fuel mixture correct.
He also says he hasn't managed to increase top end power but only midrange and he must of tried 50 different settings.
Well the laws of averages dictate to me he must have hit the right combination somewhere in all that fiddling unless he was a compleate nonse!
Sorry doesn't really answer your question. just fancied a ramble because nothing he said rang true(only half true).
Short answer is Yes but don't run it too lean
Pete.l
Most people when looking for more power try larger jets and increasing the flow of fuel through the combustion chamber. What he says in the beginning makes sence. Put smaller jets in and lower the needles by removing the shims and it will give you better fuel economy. But run the bugger too lean and it will be very economical right up to the point it burns your exhaust valves out or holes your pistons or both.
Dyno jet actually reccomend 170 mains on a std exhaust front and rear but they also claim thier jets flow differently than std main jets.
He later goes on to say he has had the head gas flowed and is running a race exhuast system. This would require bigger jets as the flow has been increase to keep the air/fuel mixture correct.
He also says he hasn't managed to increase top end power but only midrange and he must of tried 50 different settings.
Well the laws of averages dictate to me he must have hit the right combination somewhere in all that fiddling unless he was a compleate nonse!
Sorry doesn't really answer your question. just fancied a ramble because nothing he said rang true(only half true).
Short answer is Yes but don't run it too lean
Pete.l
Dont be sorry Pete, your answer will do for me. I've never been one to piss about with things unless I know they'll work, so you've saved me some money and time. I'll just leave it is it is. Anyway, this is my first litre bike (and my first V twin, if you dont count an RGV250 I had about 6 years ago) so I have plenty of time to get used to the extra mid range and speed before I start trying to improve things.
Rich.
-
firestorm_al
- Site Admin
- Posts: 756
- Joined: Mon May 20, 2002 9:56 am
- Location: Aberdeen (Scotland - UK)
- Contact:
