how do restricters actually work?

CharlieCroker

Hey all,
Looking at bikes at the moment and was just wonndering. There's a few out there that are big engined such as this CBR600 that are learner legal.
http://www.adverts.ie/showproduct.php?product=125489&cat=47

Just wondering what they do to them to resrtict the horsepower?

hi_im_fil

There are 3 types of restrictors that I am aware of.

1 - Factory restriction - This is usually a different ECU which limits the power to 33bhp. I think it resticts maximum revs, and it probably changes the map to lower the power too.

2 - Throttle restrictor - Limits the amount you can twist the throttle

3 - Aftermarket restictors - These are simply washers put on the air line going into the carb to limit the amount of air entering the engine

746watts

most common and cheapest to fit is the intake restrictor which reduces the volume of air the can pass in the inlets therefore drastically reducing the efficiency of the engine above eg 6000rpm so the engine won't rev and the bhp reaching the back wheel drops from 104bhp @ 11,000 rpm (typical 600cc) to a poxy 33bhp @ 6000rpm. After you pass your test and are unrestricted, the restrictor plate can be easily removed unleashing all the horses.

CharlieCroker

does that mean i bike with a restrictor plate makes something like a 600 feel like crap whereas a 250 thats not restricted would feel more natural?

hi_im_fil

I would say so. Some of the other lads here might be able to shed more light on it...

honeybadger

CharlieCroker wrote: »

does that mean i bike with a restrictor plate makes something like a 600 feel like crap whereas a 250 thats not restricted would feel more natural?

possible true anology ,,,iv my zxr 400 restricted at the mo and i taught it was ok at 1st as i had went from a aprillia rs 125 to it,, now i have a vfr 400 unrestricted and the poor lil zxr feels like its been strangled through the revs compared to the vfr,,poor lil bike:(

seanybiker

honeybadger wrote: »

possible true anology ,,,iv my zxr 400 restricted at the mo and i taught it was ok at 1st as i had went from a aprillia rs 125 to it,, now i have a vfr 400 unrestricted and the poor lil zxr feels like its been strangled through the revs compared to the vfr,,poor lil bike:(

Is that restricted? Hope they dont fall out on ya.

honeybadger

and just to add aswell the zxr dosent feel natural at all ,,,the bike just feels cold wile compared to the vfr and rs they put a big grin on your face

honeybadger

seanybiker wrote: »

Is that restricted? Hope they dont fall out on ya.

they mite fall out just yet seany,,im just worried in case anyting happened tho,,,,,id be banned off the road again and thats not a nice feeling lol

seanybiker

honeybadger wrote: »

they mite fall out just yet seany,,im just worried in case anyting happened tho,,,,,id be banned off the road again and thats not a nice feeling lol

call up to me. Ill ride it around without the restriction and tell ya what its like.
Call down to darren tomorrow on the new bike and I have a gander. Not to early though, need sleep. Oh and not when the soaps are on

RosieJoe

seanybiker wrote: »

call up to me. Ill ride it around without the restriction and tell ya what its like.
Call down to darren tomorrow on the new bike and I have a gander. Not to early though, need sleep. Oh and not when the soaps are on

Not too early, says the man posting at 5:30 in the morning :eek:

rgfuller

CharlieCroker wrote: »

Hey all,
Looking at bikes at the moment and was just wonndering. There's a few out there that are big engined such as this CBR600 that are learner legal.
http://www.adverts.ie/showproduct.php?product=125489&cat=47

Just wondering what they do to them to resrtict the horsepower?

I've a Suzuki DL-650 with throttle restriction, as mentioned above, it basically stops you from twisting the throttle all the way around to get the revs over about 5800, however for normal riding you don't notice any difference since the gearing on the 650 gives you decent enough torque up to the rev limit, but in 5th you run out of revs to get over 120kmh.
Keeping the revs limited is also good for fuel economy.

Stainless_Steel

Does anybody know if a combo of inlet and throttle stop is ever used as a restriction?

Or is it always one or the other?

Cuddlesworth

Stainless_Steel wrote: »

Does anybody know if a combo of inlet and throttle stop is ever used as a restriction?

Or is it always one or the other?

One or the other, it wouldn't make sense otherwise.

seanybiker

Cuddlesworth wrote: »

One or the other, it wouldn't make sense otherwise.

One of me mates had the blade thing and a throttle stop on his sv650. Was kinda strange.

jimmyendless

746watts wrote: »

After you pass your test and are unrestricted, the restrictor plate can be easily removed unleashing all the horses.

I presume here that you imply the mandatory 2yrs of restricted driving after passing your test.

There are also some good explanations on restrictors here

http://www.biker.ie/forum/showthread.php?t=95254

seanybiker

jimmyendless wrote: »

I presume here that you imply the mandatory 2yrs of restricted driving after passing your test.

There are also some good explanations on restrictors here

http://www.biker.ie/forum/showthread.php?t=95254

Me man did say once ya pass your test and can ride unrestricted he is sorted.
This isnt an anti biker.ie thing but in all fairness there is no point on him asking questions on there without licking arse, until he can ask a question.
I went from 125 cruiser to restricted bandit 600. I took out restrictors after 3 weeks so no use me telling people to stay legal etc.

n.catenthusiast

Funny got a letter from Quinn there last month although I only saw it yesterday.

Letter was specifically to remind me of 'the importance of holding a current valid driving licence to ride the motorcycle insured with us'

they quote some section of the Ts & Cs and specifially mentions the Licensing Authorities rule re the 2 year restriction.

i know one of the issues re the 2 year restriction was whether insurance companies would pay out in the event of a claim involving an unrestricted bike which should have been restricted. Seems Quinn leastways are implying that they won't shell out.

Shame will probably trade up next spring/summer and was giving serious thought to ignoring the restriction thing...