Removing restrictor cb500

[khoock]

My 2 year restriction period is up and I am considering taking out the washers. The bike is a Honda CB500 2001 and the restriction was installed by FI International.

Has anyone done it before and would be willing to post a walkthrough? I just want to judge whether it is a feasible home job or a garage job.
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A left and a right. A left. Another left and right. An uppercut to the jaw. The fight was over. And so the ranch was saved. The young intern sat by himself in one corner of the coffee shop. He had learned about medicine, but more importantly, he had learned something about life. THE END

[Noxious89123]

This might be of some help;
https://www.bikechatforums.com/viewtopic.php?t=164329

I remember talking to a mechanic before i had my bike restricted, and he said that the CB500 is eally easy to restrict, as you can get inlet trumpets that are stamped 33bhp on the side and have a reduced internal diameter. Have no iea how accurate his information is though!

Is it carbs of FI? If it's FI, it should just be washers in the rubbers between the throttle bodies and the engine. If it's carbed, there might be some other bits too.

I think FI bikes can also be restricte electronically, but not sure how they do this. (On the sv650 they just swap the cdi iirc).
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'06 Honda CBR125RW-6 ~ '00 Honda CBR600F-Y ~ '07 Honda CBR600RR-7 ~ Bikeless
'53 Ford Ka 1.3 ~ '03 Vauxhall Astra SRi 1.8 ~ '52 Vauxhall Astra SRi 2.2 ~ '53 Vauxhall Astra GSi

[Tristan.]

Side plastics off, fuel tap off, pull hose off block hose. Pull the vacuum off left hand carb, unbolt tank at the back, pull tank back and up, remove the two breathers at the back on the right of the tank and pull the tank off.

Dont need to take the airbox off (which is good cos its an absolute cunt to get off) but loosen all the clips clipping airbox to carbs, carbs to inlet rubbers and inlet rubbers to the cylinders then work the rubbers out. Do this by pulling the carbs and airbox back and up so you can pull them back off the cylinders, then take them out the side. When I did it there was a coolant hose in the way of getting them out the side, so if it's the same to you you'll need to drain the coolant, bolt on the water pump (left hand side underneathe the sprocket cover), drain coolant and undo the hose in the way.

Once the inlet rubbers are out (do them one at a time, keeps everything in place) you'll need to get the washer out (unless it's an official honda kit, which may have a restricted rubber, rather than a seperate restrictor in the rubber) bit of twisting anf jiggling, if you're really stuck try a bit of heat (drop it in boiling water or something) though it wasn't too hard when I did it.

Once you have both washers out get the rubbers back on, push everything back so it's seated properly and retighten the clips.
Refit the drain screw, ideally with a new copper washer, but you can reanneal the old one with a lighter, just make sure you use one, refill the system from the tap, squeeze all hoses to get air out of it. before you put the tank back on turn the engine on and spray all around the inlets with carb cleaner or easy start or something volitile, WD40 does at a push. if the revs peak or bog down as you spray then you have an air leak somewhere. But you should know when theyre seated properly, cos they push on nicely. Also while running it leave the cap off the coolant system, this brings air bubbles to the top and bleeds it, top it up before you put the cap on.

Done. You best do it yourself after I typed all that

[mikey 2659]

nicely written instructions.

[lnewland]

khoock you have pm
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Cg125 stolen and returned trashed
Cb500
Yamaha R6

[garycbr]

I did this a couple of weeks back, and it's definitely a home job - it took me less than an hour, including a cup of tea and chasing around the haynes manual trying to figure out how to get the side panels off.

Gary

[khoock]

Thank you all - I will have a go at it.
____________________
A left and a right. A left. Another left and right. An uppercut to the jaw. The fight was over. And so the ranch was saved. The young intern sat by himself in one corner of the coffee shop. He had learned about medicine, but more importantly, he had learned something about life. THE END

[khoock]

Took out the restrictors last week. Thanks to all for the instructions.

Additional points:
a) I left the coolant system untouched except for removing the retaining clip to allow some flexibility in the hose.
b) When removing the clips holding the rubbers connecting carbs to engine, be careful not to drop the bolts/nuts. They fall right into a hugely inconvenient space - had to replace one because I couldn't fish it out.

Quite a fiddly process but definitely do-able.

After removing the restrictors;
a) Acceleration is the same from 0-70mph but now continues to accelerate at the same rate up to 105mph (bottled out at that point) - previously rate of acceleration tailed off rapidly after 80mph
b) No change in rpm to mph ratio but seems like I am using less throttle travel to achieve the same rpm. Might be my imagination.
c) mpg has suffered as I am faster than usual (any hypermilers out there know what the optimum rpm and/or speed is?
____________________
A left and a right. A left. Another left and right. An uppercut to the jaw. The fight was over. And so the ranch was saved. The young intern sat by himself in one corner of the coffee shop. He had learned about medicine, but more importantly, he had learned something about life. THE END

[Ingah]

Struggled to follow the instructions as it's very late at night, so it might have been in there.

But you might want to check that the jets haven't been changed too. #122 jets are standard for a 1995 model at least if it helps. Honda sent me #125 jets when i ordered a restrictor kit from them (as part of said kit), as well as the restricted intakes.

So if you'd bought the bike from me, you'd be looking to change the jets back too (good job i kept the originals eh? )

[Pickledswede]

Just restricted my cb500 with these instructions and my brother's help. So thanks Tristan for putting them up!

Had a bit of a struggle yanking the intake rubbers out from in between the carbs and cylinders, and putting the hoses back on the bottom of the tank. Apart from that pretty easy job. Only thing we weren't sure about was whether the washers went on the carb side or the cylinder side of the intake rubbers so we put them in the carb side and closed it up quick before we worried about it.

Few funny noises when we first started it up but it hasn't been started in a while and we did rev it quite hard from cold (oops) fine now.

Now to get it on a dyno!

As a note we didn't touch the coolant system either but did take off the crank case breather hose. Just shoved it back on again afterwards, I hope that won't be a problem?

Once again thanks for the instructions!

[magicman-alex]

Firstly a big thanks to all (especially Tristan) for posting their experiences with removing the restrictors.

I managed to take them out following the instructions here. Fortunately the washers were not hard to get out of the inlet rubbers. I also didn't need to drop the coolant or mess with any of the hoses.

Thanks for the advice on not dropping the fiddly square nuts that hold the jubilee clips in place on the inlet rubbers, Khoock. I was extra careful doing that and managed not to drop any.

One mistake I did make was to dry and tighten up the first inlet rubber before removing the second. You can't. You can put it back into place, but you need to leave it loose to give yourself the flexibility and play to pull the second one off. Yep - I'd agree - it's about an hour's (fiddly) work. Cheers folks!