Honda-SOHC
SOHC.co.uk Forums => CB500/550 => Topic started by: Mozza on March 01, 2011, 07:26:44 PM
-
Hello just a quick enquiry about the legality of the cone filters attached directly to the carbs I keep seeing on cafe racers. Are they road legal? I run open air filters on my xt660x and they aren't technically road legal but are hidden under bodywork so I would have thought it would be the same for the cones. Plus if I do fit them is there any extra considerations I need to make regarding the carbs seeing as though they mount directly to them.
-
Don't think they come into a legal framework for the road, more likely to be observed by insurers as modified and subject to their own policy disclosure practices to make sure you are covered legally.
I'd guess that in the grand scheme of things then if original kit was not used a suitably safe alternatve would be reasonable in the view of many.
-
The only "legal" part of the induction system is that the roar may increase the driveby noise to above the legal limit---but as there wasn't one in the 70's that don't matter
-
You get up too early Bryan...
I would have said: "Modern bikes make more induction noise than exhaust noise (at least with standard cans) which is why they have such huge airboxes. For MOT purposes (theoretically) any modification that allows more noise than standard is a fail."
But as Bryan says - those rules are not retrospective.
-
That's why I love old bikes, you can use whatever filters and exhaust pipes you like as long as you don't go mad. I've got aftermarket filters and a laser pipe and the MOT man doesn't even mention it.
In addition to this you only need one working brake light switch and no side light or indicators are required. I have even MOT'd a bike with a homemade exhaust pipe. All in all this makes them very cheap to run and maintain.
-
It's why most of my bikes are pre 85 models, bypass a whole lot of the rules, I di ironically run with most of the things that you can get away without though. It just means if something stops working then I can pull it off to get an mot rather than fix a niggling electrical problem, a worthwhile concern if you only have a bike licence and don't particuarly like getting cold in the shed. I ride the wheels off the bikes in winter (minimal maintenence) and spend summer fixing them. Ironic factor with this, my 1974 honda has suffered less from a decade of all year riding in terms of rust than my 125 rebel that I'm using as a stopgap til I get some shedtime. That's needed welding in both of the last 2 winters. I geuss that quality must have been better.
-
ok then im sold i think i will get some. does anyone know where i might be able to buy them?? the bike i bought didnt come with an airbox or filters at all (or mirrors, indicators, most of the wiring......the list goes on) so i would probably be saving money and time just fitting the cones.
-
I can sell you a standard airbox if you want one, that would be cheaper I would have thought. Make me a sensible offer.
If you use a standard airbox you won't have to play around with different jets in your carburettors.
I've also got a mirror, indicators etc, let me know.
-
if they are all standard parts im going to have to pass i'm afraid as im turning it into a cafe racer. so bar end mirrors, led indicators etc is what im going for which was also one of the main reason for the cone filters as it would beef up the noise and give me a bit of a boost (however small it may be) in power.
-
Good idea, I prefer non standard which is why I have a standard airbox spare and not on the bike. I bought it in a job lot of spares and wouldn't dream of fitting it.
However, I am sure it will be very useful to someone.
-
K&Ns (http://www.knfilters.com/) were our choice back in the 70's
You will need to re-jet the carbs though.
-
Think I'm gonna have to give k&n a call they don't seem to have them on the website at least not for my bike, although I think I'm thinking a bit far ahead yet I have only just stripped the bike down ready for sandblasting. I'm just seeing what my options are.
-
I use SB filters on mine and I must say they are marvellous.
-
Which ones do you use? First time I have ever heard of that company. If you don't use the standard airbox how are they mounted?
-
Custom fastners in Newtown sell S&B filters plus a few other goodies for the 500/4 like shock absorbers. Be aware that to fit S&B filters you'll need to kinda squash them sideways to clear the frame. I fitted a set for a while but decided the re jetting was too much of a chore so went back to standard kit (still got them in a box somewhere along with a custom battery and elecctrics boxes that were to go on a 550 chop I gave up on). I mainly got them as I was testing a few unknown engines in the bike and was right royaly fed up with fighting the standard airbox into place. Another place I think is closer to you that may well be worth a visit is JW motorcycles near Borth. He builds racing speck frames for classics including the 500/4 as well as stocking a good range of parts. Also knows his onions when it comes to older (and probably new) bikes.
-
I didn't realise he did cb stuff I thought it was Just pre mot stuff and servicing I actually had his card in my wallet a while back. I took my hornet up there when I had it to get it serviced a couple of years ago. Excellent call on that one mate I had totally forgotten about him! I will check out custom fastners too as I'm in need of some new shocks and don't know if I trust the Chinese replicas they have on eBay.
-
They are S&B universal ones and they just go straight on to the carb.
Because the frame gets in the way I had to cut a little bit of rubber off on the outer ones but then had the carbs balanced and it seems to work fine. I had to use different jets but with that and the laser exhaust the mid range power is noticeably better.
-
Awsome thanks for all the replies even though I have only been on this site for a couple of days it's been a massive help, cheers!!
-
Look on Jw's website, they do all sorts of aftermarket kit that they don't seem to have in the shop. Dave Silvers for the standard parts.
-
I think I will go see him next week actually he's literally only a couple of miles down the road from me plus it will give me something to do while the frame and swingarm are at the sandblasters. Is it difficult re jetting the carbs? I'm not very experienced with engines or carbs but more than willing to give it a go.
-
Not difficult, but if you haven't got a dyno, it's trial and error.
Getting carbs on and off is the worst bit.
-
Yeah It was a bit of a pain taking them off the first time I can see it becoming a nightmare if I have to do it 3 or 4 times.
-
if they are all standard parts im going to have to pass i'm afraid as im turning it into a cafe racer. so bar end mirrors, led indicators etc is what im going for which was also one of the main reason for the cone filters as it would beef up the noise and give me a bit of a boost (however small it may be) in power.
If you're cafe racing it I've just ordered a set of these http://sohc750.net/shopping/steel-dragon-performance/original-velocity-stacks/ (http://sohc750.net/shopping/steel-dragon-performance/original-velocity-stacks/) for $88 for four delivered and including gauze and set screws. That's actually around
-
Nice I bet they are loud, was toying with the idea of velocity stacks but they will probably only have a small protective screen over them stopping dirt and other grime getting sucked into them won't they? And not a proper air filter element. I live in the countryside where the roads suck and are always covered in dust, mud etc. Let me know how they sound though with a set of aftermarket pipes I bet it's amazing.
-
OOh dear...gotta say I'm not with you on this. I hate those K&N S&B filters. The induction racket (I wont even say noise) is just horible. A mate of mine bought a 79 GS750 a few years ago and it had those bloody things on. First job was to source an original airbox. Not easy.
a) To get rid of awful whaaa! whaa! induction rwharp horible noise... :o
b) So it carburated properly across entire range ... main jets only fix a minor % of carburation, for road use its almost everything but the main jet that you need to get right.
-
Get a cup of coffee and settle down in front of your screen.
Comfy?
Now read this:
http://forums.sohc4.net/index.php?topic=5410.0 (http://forums.sohc4.net/index.php?topic=5410.0)
[Carb FAQ from .net site]
-
I'm used to hearing the thump of my single cylinder xt660x with scorpion exhausts and stage 1 and 2 filters which makes a LOT of noise. When I first heard the 500 running I was impressed with the smoothness but not the volume, I think it's a generational thing hahaha the bike is 10 years older than i am! I picked the bike up as a project to learn the mechanics so I'm looking forward to tinkering and tuning everything to work in synch with everything else.
-
Jim fitted some K&N type filters to his bike... http://www.sohc.co.uk/index.php?topic=3122.msg11171#msg11171 (http://www.sohc.co.uk/index.php?topic=3122.msg11171#msg11171)
-
Wow that bike is lush! I asked in another thread about chopping the rear mudgaurd off like that and if that's a uk legal bike I'm going to go ahead with it. Really nicely put together props to the builder.
-
hahahahaha thanks.
legal, brilliant.
whats that all about then ???
-
Just leave the rear muddy out for that look! sell the old one If you have one along with most of the rest of it if you are set on a radicacally modified bike. I must admit I'm tempted to cafe racer the remaining 550 I have yet to cull. For the 500's though I think the bikes are quite nice in pretty standard speck. I'm not sure why but the 550 never held that appeal for me. I think the 550 tank would look better for a cafe racer with it's smoother filler cap desighn and taller forks - would suit a set of clip ons. The 550 front muddy is shorter too.
-
hahahahaha thanks.
legal, brilliant.
whats that all about then ???
Did it pass the MOT I mean. Would love to use a few of the ideas you have on my own bike- same filters and removing the rear mudgaurd. It's a really nice bike.
-
Would love to use a few of the ideas you have on my own bike- same filters and removing the rear mudgaurd. .
So why don't you?
Don't get hung up on 'legal', most cops have no idea about construction and use, or even the finer points of law and if it's passed MOT that's enough, if it doesn't you take the MOT testers advisory, put it right and go for a re-test.
Two examples:
My bro-in-law was stopped on his '75 Triumph trike in Southport, copper says "You know why I've stopped you don't you?" Dave replies "Actually no, I know I don't have indicators, but it was built and registered before 1986 so I don't need them, it DOES have a handbrake, it has an MOT and is insured, it's also tax exempt, so why have you stopped me?" "Because you're not wearing a crash helmet!" There is then a 10 minute war of words culminating in the policeman radioing the station to be told "Actually, the rider is correct, he doesn't need a crash helmet on a trike"
My neighbour got stopped for overtaking on chevrons, again the copper thought he had my neighbour bang to rights, until it was pointed out that it is legal to overtake on chevrons, providing there is a broken white line on your side of them.
So, forget the 'legal' hang-ups and go for it!
-
I'd try asking the place that will actually test your bike tbh, saves taking the bike along only to have to drag it home again just to add some silly part for the test, something that inevitably has a raindance effect of 10 days downpour so your retest results in a good soaking. Other thing to consider is how you then intend to use the finished bike. Minimal muddies may look good but can result in getting drowned by road spay (or worse) in the wet. If it's a weekend plaything for sunny days then inpracticality may be ok. I take the view that keeping the tester happy is well worth the effort, even if I put the stuff he wanted added streight back in the shed once I'm home, that's partly because good testers can be hard to find out this way so I'm not going to risk upsetting them by arguing the toss about who's right on a technicality.