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jetting question?

PostPosted: Sat Jan 31, 2009 8:29 am
by captain howdy
Hi Guys :-D
I'm new here and so the questions begin, I've just got a 02 plate Mastiff and it's gotta a Micron can on it with no Db kiler,
first gear just seems to bog down?
My mates Baghira would rip ya arms out in first there's absolutely no danger of that with this,
does it just want Dyno jetting? is there any recomended simple mods when I had my CCM there where simple things to do, the TPS to check airbox mod etc thanks Chaps

Re: jetting question?

PostPosted: Sat Jan 31, 2009 2:20 pm
by Linegeist
Hi there!

Possibly a silly question, but have you checked the drive sprockets to see if somebody has futzed with the ratios for 'more economy' or 'longer legs'?

Bob

PS: Welcome to the forum. ;-)

Re: jetting question?

PostPosted: Sat Jan 31, 2009 3:53 pm
by hutchy
Hello and welcome,

What exactly do you mean when you say it "bogs down", do you mean it just will not pull away cleanly , does the engine cough and fart or does it just rev it's nuts off and go nowhere fast?
It could be a number of things, do you have a standard can to put on it so you can see if its the exhaust and how does the bike differ from your pals,gearing, exhaust, carb mixture screw settings and so on? If someone's messed with any of these things you could be a while sorting the problem but at least if you copy your pals bike for settings and maybe the odd swapped part you will be able to get to the cause quicker.
In the meantime ask as many questions as you can on this forum (lots of clever boffins here)and try to be as clear as possible with your explainations so people can reply with helpfull time saving stuff so you don't have to go round the houses just so sort a fairly simple problem.

Good luck........Hutchy

Re: jetting question?

PostPosted: Sat Jan 31, 2009 4:44 pm
by MSW
If the only change has been the can, you wouldn't think that "bogging down" would be the issue. If anything, a more open exhaust should cause you to run lean. Might just be an adjustment issue. Or maybe a previous owner has already monkeyed with the carbs?

Although these CV carbs have limited upside, there are a couple of mods out there that can give you better/quicker throttle response. I'm no expert, but I've done one of them (the tunebike carb mod), and it did help. Now the response on mine is noticeably better than stock.

Give them a try: http://www.tunebike.de

Actually, I think it's not so much changing the jets that helps. it's the spacer/venturi tube mod to the primary carb that seems to make the most difference. Changing secondary main-jet sizes should only be done to compensate for a freer header/exhaust can. I've heard that some guys just do the primary carb/spacer thingy and leave the jets alone and still get good results.

These guys sell another carb kit for the Baggy/Mastiff that is essentially the same (I think Dynojet supplies the parts for them): http://www.off-the-road.de/vergaser_vergaserkits.html?&L=1

Good luck!

Re: jetting question?

PostPosted: Sat Jan 31, 2009 6:49 pm
by captain howdy
thanks for the replys
by "bog down" I mean it sets off but it jus seems to hit a wall with out hitting any kind of revs
so change gear and it pulls then stops again just won't hit any kind of revs/accellaration,
shame as I really wanna like, it as I said I've had a CCM i've also had a 750 super Tenere and a 350 aprilia traily just want a
good run around with a bit of poke as i'm happy to stickat 70/80s mph
i've just come from a bandit 1200 so i appreciate it aibnt gonna be as quick but it defo just aint revving "clean"
Thanks

Nige

Re: jetting question?

PostPosted: Sat Jan 31, 2009 11:35 pm
by Bill Jurgenson
maybe a silly question, but havechecked if the 38hp reduction plate is installed?

Re: jetting question?

PostPosted: Sun Feb 01, 2009 2:50 am
by rodge70
even sillier question,are you confusing bogging down/hitting a wall with rev limiter operation?

Re: jetting question?

PostPosted: Sun Feb 01, 2009 4:30 am
by captain howdy
it does feel like it's hitting a rev limiter but if it is it's very early? and reaches no kind of power :?

it could have a restrictor fitted , my mate had a Bandit 400 restricted to 33BHP after pasing his testand it does "feel" similar to
how that was to ride i.e would rev out in gears,
where is this restrictor? and I'll check it out,this could be a simple solution(he hopes)

thanks
:-D Nige

Re: jetting question?

PostPosted: Sun Feb 01, 2009 4:45 am
by captain howdy
used the search option and found that the restrictor is in the right hand larger carb so I'll have a look for that can I see without dismantleing?
also read about damaged diaphram/wet diaphram on same carb causing the slide not too lift another avenue to explore

Nige