Fuel starvation

[Repsolnc30]

Hi I seem to be have a problem with fuel at approx 100mph almost as if the bike is starved of fuel. I had a similar problem at a lower speed but that was sorted by refitting the air box scoop. Basically bike works perfect until I hit approx 100 them just loses power and cruises at 55-65 mph for about 30secs and then will accelerate again, the fuel hoses are all new so no problem there and as I said I have refitted the air scoop with the larger of the flaps by the carbs is this right or should it be covering the plugs?

Is the hrc fuel tap mod worth trying ?

Any help with above would be great !!

[richyrd5]

When you got the air divider of geoff did it come all as one?as it only goes on one way really.the larger flap goes over the head and somewhat down a bit into carbs.but then the smaller flap also goes down behind the carbs.but lays over the crossmember where choke cable ties to.the flaps direct air to cool the V and the carbs.but i think im right in thinking that it also stops the hot air going into the airbox.im sure someone will come through with something COMPLETLY different tho!!!

[Icemaestro]

Have you done the fuel tap mod? Common problem at high revs is for the carbs to run out of fuel, which to me describes your problem...that or the air box set up, but I used to notice it at around 60-70mph not 100 when I messed with my scoop etc

[Repsolnc30]

Before the scoop was fitted I had the problem at 60-70 now after I've fitted the problem is at 100 ?? Have not done fuel tap mod as I wanted to check here first. A few people have said that the larger flap should sit over the plugs ?

[richyrd5]

Yes it does.the back of it slides down a bit to the V.But its the smaller one that goes down more.

[Repsolnc30]

So covering the plugs is wrong it goes towards carbs ?

Any chance of someone posting domes pics ?

[arsey30]

The rubber flap keeps the warm air from the air box [less dense]
Fuel starvation occurs when flat out for a while, not at 100mph, the standard tap delivers enough fuel for road use, the HRC mod can give rise to fuel leaking into the engine.

[royster81]

Have you done the fuel tap mod? Common problem at high revs is for the carbs to run out of fuel, which to me describes your problem......

Do not do this

Make sure all the correct flaps and scoops etc are present and if it still doesn't ride right you have something else to worry about but ie carbs or electrics but I wouldn't advise doing to tap mod to anything.

[Repsolnc30]

Thanks arsey have you a picture of where the larger flap sits ? The carbs have been checked and set up on dyno, seen bike hit top speed on dyno but on the road it won't !!

[royster81]

It might have something to do with the fact there's little wind directed on the bike when on the dyno but when riding on the road at 100mph+ there's a lot of wind getting pushed at those carbs.

Ref the flaps, one flap hangs down over the plugs and the other flap hangs down towards the carbs.