My Vega stoped going flat out... Any thoughts?

[Supereibar]

I took the vega for a spin yesterday. 94 kms (about 60 miles) some flat out on 80km/h (50mph) on the motorway. It was precisely on the motorway by El Prat (passed the airport) that the engine stoped. I was going flat out and suddenly the engine seemed to go silent. I instantly pulled the clutch and tried to go back in gear, but it made the same sound as when it runs out of petrol. Didn’t seize (meaning, the rear wheel didn’t lock up), just stopped. I dodged the million cars passing right and left and pulled on the layby to kickstart the motor. I thought it had hit reserve, so I turned the tap, kickstarted it and it started first kick again. When I got home, I turned the tap back to the “on” position and realised that I still had petrol to go until I got to the reserve, so the cause of the hault could have not possibly be due to running out of fuel… Or could have?

Now this just gets me because the engine is standard (with the exception of polishing of the ports, a Sausage speed electronic ignition, a higher main jet and multiple hole inner filter top hat piece, the one that is shown on the 60’s tuning & performance maual). I rebuilt it last year, new conrod, trued crank, new bearings… After running it in, and using it off and on in Mallorca the whole summer, I have never had this issue before.

The only possible explanation I have is running out of fuel on the high rpm range. I was going flat out and possibly the engine was calling for more fuel? Does anyone have any suggestions?

I was thinking of taking the whole thing apart again, and go radical on it. New crank, new piston, new bore, new bearings… But now, this is me being paranoid, and maybe the answer is to upjet the carb.

Regards,

J.

[firekdp]

The only possible explanation I have is running out of fuel on the high rpm range. I was going flat out and possibly the engine was calling for more fuel? Does anyone have any suggestions?

It's possible that you're over running the supply at that speed. IE. the float bowl is emptying quicker than the tap/system can supply.

[steviegp200]

sounds plausable fuel wasnt flowing fast enough for demand of motor or air bubble in fuel line never rode a vega on the road (id prob crush one lol) but i can guess it would be vibrating quite a lot could it be fuel frothing in carb if its solid mount? had rings nip up before not siezeing to barrel scoot just died sat for a bit till piston cooled n rings released took a while though maybe just one of those things that happens once n never does it again hope its nothing serious mate

[bristolmod]

Jaime

had a similar problem on one of my TV175's

turned out to be a buggered fuel tap which, although it appeared to work OK, was not flowing enough fuel to keep up with the engine at high RPM

I sorted it by fitting an old genuine one I had knocking about after dismantling it and checking all the drillings for crud etc- has worked fine since.

TBH I'd rather fit an old Innocenti item than a remade "fast flow" in view of the build quality on the remade stuff.

Have a good Chritmas mate- I'll be in "that" bar on Boxing Day with a cold SM.

BTW- any joy on those old "Penelope" disco stickers?

best

Chris

[Tosh]

just check that the handle part of the petrol tap what you get hold of to turn it on is not slipping on the shaft,it happened to me last year
thought i`d turned it on to full but when going down the road for about 600yrds it stopped wondered what was the cause was by that time it had filled up again
and it started only for it to happen again.

Hope this help Paul

[Spanish Fly]

Surely if you were suffering from fuel starvation at high speed it would have holed a piston or siezed. To just cut out like that sounds more like an electrical problem to me. Maybe something got hot coupled with vibration and went open circuit then reconnected when it was cooler?
SF

[Supereibar]

Just reading all your replies I think it might be a fuel starvation issue. Someone from a different source has said exactly what firekdp says. SF leans towards an electrical issue which I value as well as a potential reason. What I am not sure about is honing a piston without enough petrol going in the cylinder? Are you sure that happens? It happened to me once on the vega as well, when I had a cut on the petrol line and fuel was leaking. It did exactly the same thing it has done now. It just didn’t have enough petrol.
Also I want to make clear that I didn’t wait more than 2 seconds to restart the scooter. I stopped on the layby, put it on the kickstand and started it right away. Engine was probably still just as hot!

Thank you very much for all of your replies. Kind regards to all!!

Chris, I completely forgot about the Penelope sticker, but don’t worry, as said by Marcelus Wallace in Pulp Fiction: “I am on the motherfucker!”.

J.

[thackers]

Hi Jaime. Do you have the fuel line running behind the rear shock ? It could be getting nipped if it's tight next to the mudguard and shock spring. It could be also a sign that your low tension coil is playing up too.

[cezeta]

make sure your petrol cap has a breather hole. if not it will do what say. little b@5t@rd hole cost me a full rebuild on one of my vegas