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[AMCQ46]

nice vid..........revs like a race bike, impressed

[benny hedges]

mate had a go on it before and shat himself lol - forgot to tell him about the 1/4 turn throttle
guys minted tho so i said if you drop it im having your snooker club!
he took off and the wheel came straight up lol, he came back & said crouton me wtf have you done to that, it;s like a fkin crosser!
yes it does pick up quick, very pokey in the middle and pulls well to the limiter but feels lean on top.
havent got any bigger jets - its on 190/5 atm & 48 pilots so only thing i can do atm is put my k&n on instead of the bmc & see if it's any better on top - talking like 8500+ so it's moving some by then!
feels a lot more tractable though and seems doing the shims proper has really quietened the motor down.
all in, well worth the effort but need a dyno run to sort the fuelling, see whats going on, might well be over-rich but it isnt showing on the plugs, they look bob on.

only problem today was my back light fell off lol. had to strap it back on with the bungee thing from under the seat!
and i forgot to take my clear visor or i'd still be out now. only burned 2 tanks today

[Pete.L]

Sounds brill Benny Keep up the good work

Pete.l

[MacV2]

Not jealous at all, not a bit.

Get it measured....

Pffner, Pffner, Ohh Mrs ect ect

[benny hedges]

another good blast out, clocked 300 miles now with these in.... verdict?
mmmmh, i'm not so sure.... definately pokier in the middle but i can't make my mind up on the top end.
seems to be more of an effort to get it to redline in 5th & 6th?
on my private road test it got to indicated 160 in 5th, right on the limiter, but didn't make it to the limiter in top, whereas before it flew there

not sure if it's the new cans that just make me think it's not right, or if these cams are designed more to improve midrange...
they definately do that, but i tend to ride more around 7500 to limiter so it seems well, how do i put it???
undecided atm.
might have to whip the tank off and do like an after & before test & see if that helps me make my mind up.
if it hits the limiter in top easier then the cams will be put away until i get the je pistons.

just another example, usually, on one particular private sliproad, i take the private roundabout at about 45-50, then by the time i hit the bottom it's doing 150.
last night it made 120
i went back & did same test and same result.
now as i posted earlier, it feels like it's running lean at the top end - i think the way to get it right is pop the oem ones back in, do a fuelling run on the nearest dyno, to get the mix right, then try them again and see what the difference is.

it really comes down to riding style tbh, if i was a low rpm pootler then i'd be made up with it, but as i like bouncing off the limiter in every gear i dunno....
maybe it's the advance rotor???? very undecided if i like it or not atm

[tony.mon]

Sounds as though it's having trouble breathing properly.

Maybe a full race system and head job would make things better, trouble is that's a lot of money for an exhaust, and if you open the heads up then it's no better you're up for a pair of replacement heads.

You didn't get a baseline reading on the dyno before fitting, did you?
A comparison might help.

Also are the carbs set up since fitting?
Might need bigger mains??

Sorry to hear this, was looking forward to slinging a leg over this at some stage (stage 2, probably).


Or maybe they'll only work properly once the turbo's fitted?
Won't need high comps then.....

[benny hedges]

Sounds as though it's having trouble breathing properly.

Maybe a full race system and head job would make things better, trouble is that's a lot of money for an exhaust, and if you open the heads up then it's no better you're up for a pair of replacement heads.

.....

funny you should say that.....

......... today while it was raining i thought crouton it, i'll take em out, put the standard ones in, then get it up to lancaster for a dyno run to get the fuelling bob on....
got as far as tank off, carbs off, rear cover off, inlet cam out... was just shimming the oem back and had a chat with marlbro who suggested it could be because i'd fitted shorter cans at the same time...
it went like stink with the lasers on (full lenght cans)
now i've fkt about with tuning rpm with exhaust lengths on 2 strokes and know how critical it is, esp at high rpm, but thought on 4 strokes it's just the downpipe length that matters....

appaerntly not.
took a bit of persuading, but then i thought, it's a 4hr job to do the cams & re-shim, vs a 1/2 hr job to swap pipes.

so i put the new inlet cam back in & set it up, retimed it etc, swapped the pipes and put it to test.
back after the break...









ok. right, guess? better? worse? same?

better. much better. in fact bloody brilliant.
the midrange boost carries on right into the red.
i'd like you to ride it next weekend tony and see what you think, and the vac valves...
i think you'll agree it is a LOT different lol

so i/m very surprised that such a minor mod can have such a detrimental effect on the rev range - it just did not want to pull high rpm in top, whereas now, indicated 170 in top and thats with me (fat little b8stard) on it, grinning like crouton and feeling quite chuffed with meself for listening to someone else for once in my life!

so i was wondering - anyone else here who wears stubbies - clivey for instance, do you notice an unwillingness to hit the limiter? cos if you do, there's your answer
so glad i didnt refit the oem cams cos with the same cans i wouldve had the same effect, minus the midrange boost.

[sirch345]

I like it

break is over now, so what was the out-come

Chris.

[benny hedges]

better.

[benny hedges]

the art ones i was running aren't that stubby tbh, 15" but only 90mm diameter.
they had no baffles in but were to fkin loud, was getting headache even with plugs in, so i put some baffles in to hush them a bit...

nice pipes but i think i'll stick with the lasers for now.
if someone wants to take them off me - pm.

when you say yours ran crap, do you mean the fuelling or the rpm?

[benny hedges]

Also are the carbs set up since fitting?
Might need bigger mains??

.....

fuelling?
it hesitates slightly under 2000rpm, so i'm running with an idle around 1700 cos i've already had one instance where it coughed and stalled on me while i was down to the pegs on a slow turn - nearly had me off, if it hadn't been for the fact that ive got legs

that's with 48 pilot jets (standard are 45s) and the screw near enough hanging out!
i put a blob of instant gasket over the screws so they don't come loose...

mains? i'm running 195 / 190 but theyre dynojet mains so not sure what that equates to.
used to have a tin full of kehin / mikuni jets that id collected over the years but i'd rather get a dyno printout off it to be sure it's the jetting that's off befre i start fkin about wasting time & money on jet kits with sizes i'll never need.

after putting the laser cans back on it runs sound, pulls very hard and goes a ton over nsl easy (indicated lol) - i ordered a speedo overlay from ebay so i'll set the speedo up proper when i cba.

economy? with the 19L tank, if i ride like a rock it returns approx 85 miles before the light comes on, but that's using the level sensor off the 16L tank, and i usually put in about 12 - 14L at the pump.
riding like a granny in a rocking chair it gets 120+ before the light, so approx 10 miles / litre which isn't bad imo.

later today i'll put the +4 advance rotor back on and fit a new clutch cover gasket (leak!) and it should take off even quicker lol!
look forward to getting it on the dyno tho, definately feels a lot more powerfull than standard.

looks a nice shiny exhaust system that mike, wouldn't mind some shiny downpipes meself - they look a bit rough underneath atm, but then again rest of it is a shed anyway lol!

[tony.mon]

Good on yer, pleased it's better.

After I'd posted I also thought about airbox size, that'd also restrict max rev breathing.

I guess the main thing with any mod like this is that they're rarely fully effective in isolation, one thing leads to another and you've ended up with a Stage 3, completely unrideable on the road but brilliant on the track, if you're not careful.

But **!$*bugger*%!!* as I was congratulating myself for not contacting the seller and gazumping you on those cams, reading your first reactions!

Ah well, once I get the regrinds back from Newman Cams (can't really recommend, he's cheap but can't work to a delivery promise- two weeks over promised delivery now, and not returning my calls) I'll dyno and we can compare notes.

See yer Friday.

[benny hedges]

just bolting it back together after putting the advance rotor back on, then a quick blast round my private track!
i know it will take off a lot quicker, but again, if it fks up the top end it's coming out again lol.
there's madness in my method....

found another possible cause for an unexplained misfire.....
mine wasn't misfiring, but i noticed on the ipg pickup, on the magnetic tip, there was a few bits of swarf on the tip.
i could imagine on a bike with more miles, there would be a lot more metallic crap stuck to it and imo that would definately cause an ignition misfire....

i mean the square 2 wire magnetic pick-up inside the clutch casing, that picks up a signal from the revolving advance rotor....

[sirch345]

better.

I'm pleased too hear it Benny
A bit of good fortune that Ian (marlbororman) came up with that suggestion and you took his advice.

Chris.

[marlbororman]

Lol, it could of backfired on me though Pleased it worked out ok though. lol. Be interesting to put the cans back on to double confirm though, when thats the last thing that remains left removed from the bike ;)