rocketron

Many thanks Mike, have had this photo in my archive for years and never knew who it was! Ron

Who do you think this is?

Not much point in having an air filter if it is dry.It only catches small twigs,wee mice and spiders.As for spraying the inside of the airbox with chain lube it makes no sense.All the dust will collect in there and it isnt easily cleaned.The air filter is easily cleaned with a tupperware tub of petrol and a pair of rubber gloves,turn it inside out before cleaning.Any oil will do,as long as it is not too thick,air filter oil is the stickiest thing on the planet and I dilute mine with petrol 2:1.I still manage to get it on my boots,the garage floor,the frame,on the exhaust etc...Who the hell designed these Scorpas anyway? That airbox is a bollix. I must try and find a second hand airbox and do some work on it....... Need a pint first.... RocketRon

The airbox is made from two pieces of moulded plastic welded together and the inlet to the airbox (where the car rubber joins) had not been tidied up after it had been made.I used a knife and needle files to smooth off any rough edges on the flange where the carb rubber attaches. To my mind it is bad design from the very start.Most carburation systems require a clean straight flow of air into the carb and on the Scorpa the carb rubber always distorts and restricts the flow.You just have to play about with it to get it as smooth a flow as possible.It works but it could work better if someone could redesign the whole airbox,carb rubber assembly.The problem is the rear shock absorber,there is so little space because of the room it takes up and that is why the carb is angled out of the cylinder barrel. Of all the features on the Scorpa this is the one bit that could be better thought out! RocketRon

Hey Jools, Am so glad you found the problem after my post! Being in N Ireland I couldnt go and see NB but I asked him if he had had similar problems to mine with the carb rubber and he said he hadnt. Mine occurred about March last year and to my mind the casting of the airbox was all wrong.I had to trim it with a Stanley knife to get the excess plastic off it before reseating the carb rubber.All 06 Scorpa riders beware! My bike ran better than new once I had cured it,beats me how they let them out of the factory that way........French Quality Control is merde. I hope your bike is continuing to run well. RocketRon

HI Jools My 06 Scorpa also had a weird fault.It was fine from new but after about 3 outings it would start fine,then after ten minutes or so it wouldnt rev past half throttle.It would four stroke like mad but then if I let it cool down it ran fine the rest of the day.I am still mystified by this but I had changed my two stroke oil from Belray (80:1 mix) to Castrol 747 (100:1 mix).I also noticed that the carb rubber to manifold was very squashed and it looked like it was restricting air flow.I went back to Belray 80:1 mix and reseated the carb rubber so it wasnt so squashed.No problems since. Maybe the bike had been partially seizing? I never knew the exact cause as I changed two things at once. Just my thoughts. Good luck Ron

Ok,I have it "less kinked" now! One last question.......what are you all running your mixture screws at? Mine seems to have the best revs at 3 turns out but the manual says about 1 and 3/4 turns. Thanks Ron

Thanks all, It definitely isnt the tank breather.That inlet rubber is badly kinked but I can see no way to avoid it! Are your's all similar or are they a nice cone shape? I did have the carb off due to my earlier "woes" but am sure I have it pushed as far home as I can.I did locate it into the groove on the reed valve manifold,at least I think it did!Will check.....

Hi y'all,me again with my 06 Scorpa which had it's carb woes and cuttin out etc... Well,That seems to have been a premix problem and since going back to 80:1 all has been whoop di do.Until recently.. Ok,here we go.... The bike fires up on second kick,turn the choke off real quick (else it will die) and get it on the throttle.Really boggy for about ten minutes or a good open throttle rev and then she's clean. What I notice is that at low revs or blipping I can hear the carb pullin air,you know like if there was no air filter in,an induction noise.Also the bike has got lousy throttle response.The stuff I used to ride in 2nd gear now requires 1st gear to get the instant response.Mid range,top end power is all perfect. Also,that horrible rubber manifold between carb and airbox is almost squeezed flat.Have tried twisting it round etc.. but it is definitely kinked.There is no way to move the airbox back so I'm at a loss there as to if it's normal or not to have a slightly squished carb manifold. My 02 Scorpa didnt suffer any of these problems,was responsive,the manifold didnt seem to be so tight fitting and I dont recall it sucking air when I was on 1/4 throttle. Oh,another thing,mixture screw,am runnin about 1 and 3/4 turns out although it doesnt seem that critical.And I havent got too much oil on the air filter! Could it be reed valves? Crankcase losing pressure? Any ideas before I fire it back to the dealer? I've done all i can and I am stumped. Thanks,will really appreciate some help on this Ron

Yep,it was Birkett's who gave me the price for new one! Second hand ones from a TYZ are as rare as hen's teeth! Have repaired the original now.Dont know whether to leave the battle scar or try and repaint the whole thing.... Ta for help R

The Alcy Man doesnt drink enough in my opinion.If he did he might stop whopping my ass every Sunday on his extremely noisy 4art. Put the restrictors in again,please I may have to borrow your liquid metal (if you havent drunk it all) to complete the repair of my smashed clutch cover on the Scorpa.I really must try less hard to break a rock everytime I ride over one...... See ya on Sunday,hope you have a mega hangover..... Rocketto

Hi,Guess what? I managed to get the Carb Woes all sorted out thanks to the site here. Have gone back to 80:1 premix and bike is going great.Too great in fact as I managed to launch it down some rocks and dented the clutch cover on Sunday.It was quite nasty as it also broke one of the studs off the clutch hub.The casing wasnt badly damaged and only slight oil seepage rather than leakage.The clutch is repaired now (new clutch hub) and i am about to repair the casing (new ones are

It seems said member (alcholic) prefers to remain anonymous.I mean why else would one drink? Or is that oblivious? Just a sec....

Yep guys,kind of agree.First step is to change premix to around 75:1.I was running the 100:1 mix in my old Scorpa with no bother but it was a well bedded in engine.The odd thing is that the 06 bike runs fine once it gets over the fuel starvation thing,but that could just be the barrel heating up slower than the piston and rings.... What you all running in terms of mixture screw settings? 1 3/4 turns out?? Ta again Ron

Hi all I am the proud owner of a new 06 Scorpa,I had an 02 one for a year and I just love em but have a carburation prob with my new one.... Bike starts ok,sounds dead flat on the choke and have to get the choke off fast as it will bog the engine but once choke is in she is fine.After ten mins or so it seems fuel starved,pinks a bit,then goes really dead as if no fuel getting in.If I can manage to keep it going it seems to clear and runs well for rest of the day.Have had carb off,no problems in there,have tried running with tank breather off,no better! I am running on Hi Octane fuel,100:1 Castrol 747 and am totally mystified by this problem.It only seems to happen once per outing.It is definitely not water in the carb or air filter as i did all the carb checking etc.. before washing the bike. Any ideas? What is best setting for mixture screw? This is first time I've used 747 oil at 100:1 mix.As it is a new engine I hope it isnt partially seizing? Ta for any ideas!! Ron