yes I did search, yes I understood the posts (not my first rodeo).

However not all of it was clear.

My bike seems to be a French import. French as a guess as it has French labels, some English but no German labels. Imported into the UK in 1997

Bike details,

Chassis SC21-2******
Engine SC1E-2******

Completely standard aside from Nexus back boxes.

The Airfilter has BOTH ends open (full power air filter). As a quick test I removed the filter completely and ran it up the road (I live right beside a national limit road) and it made no difference.

When I first got the bike I bought replacement airducts as mine were missing (all open free flowing new ducts no restrictions within).

The airbox itself, looking inside from the air filter opening looking up there is a white ledge within, do full power models have this? Air box to the right of the opening and up has this part number on it HMMM5E1

The pipes from airbox to carbs are full size no narrowing or ledges.

The carbs, I have had them out and cleaned and balanced them, however I never took note of the jet numbers. I will take them out and do so but this may not be for a while since the rain is constant more or less just now. Slides all work as they should the bike is smooth as silk although doesn't pull well from lower down. Also full throttle is being achieved.

The number on the casting is (Keihin carbs) 80A (then an A in a square box) B and then it looks like it could be a 3, B or an 8, the stamping is poor. Then finally a funny symbol. So looks sort of 80AAB8

The carb rubbers, these are open, not got a great picture but here is one when I done the head on it, as you can see they appear to be the full power ones



In one of the threads there was a mention about the cams possibly being different, is this true?

Engine itself, silky smooth, slight rattle at lower revs seems to be the alternator chain despite receipts of it being changed 5 years and less than 10k miles ago! All valve clearances correct, compression figures since the head was refitted figures in PSI, 155, 150, 155, 150. All well within tolerance and of course when the head was off all chambers leak tested. Basically the engine is fine is what I'm getting at.

The exhaust downpipes and collector are in good condition no dents, no washers or anything. Both back boxes free flowing.

The bike is just not what I wanted, its just not fast enough. Certainly not 130 ish bhp in the engine room.

My other bike is a 91 hp 1984 CBX750FE which is slightly slower in acceleration but nowhere near 40 hp slower. The CBX is also a heavy beast only 20kgs less than the CBR, so its not like its a modern featherweight to this old dinosaur.

Now the interesting point is I know of others that had these CBR's in the past and after they were chasing me on the 750 they said that its probably faster than the CBR! I said don't talk nonsense. However it seems to be true.

The 750 also pulls better from lower down, I can use the 750 in 6th gear at 20 mph full throttle it and it will smoothly (although not overly quickly) carry on up to 130 mph (which is all it does), the CBR won't do that, it needs to be in 2nd or 3rd at those speeds and it pulls up to 130, not had the conditions to go faster although it seemed willing to go faster, just not with enough urgency. I doubt very much that it would reach 155 mph unless it was down a bike hill and there was no one on it.

The handling is fine and when riding I can pass other bikes easily in the twisties although it does scrape easily, its just when a straight comes up other newer bikes can then catch me and pass then are long gone until the next set of corners where I pass them again, generally when going for it I change up just before the redline (10,400 rpm roughly) so its not like I'm not revvi0ng hard enough.

So basically I want to know if

1. the cams ARE different

2. if the airboxes on full power models have that built in plastic ledge thing (its meant to be there, its placed in then the 2 halves of the box were formed together so its not aftermarket)

3. The carb differences between the full power and restricted units, jet numbers, needle details etc

4. if this is the best it gets its getting sold on which I don't want to do.

 

^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ +100

Yup last option ........would seem to be the best since most questions seem to come already answered ! kinda

Funny thing is if I had the jets out you can be damned sure I'd be checking the sizes rain or not !................ whole post is fluff

 

Ummmm we had one of these last year with that ever sooooo amazing CBR review !!!

Ya know what they say ! looks, smells and sounds and all that jazz - this ones a potential
qualifier right here.
only comment I can make on the above is simply

 

I fail to see what the issue is I asked a question and for some reason none of you wish to answer it.

Its ok for me to answer other peoples questions but when I ask one I can't get an answer.

As for the jet question, working on cars, trucks and bikes all day I forget things, so yes I had them apart, was going to do a wee how to on it but why bother, I never wrote down the details during the strip I just cleaned the crap out and put it back together.

 

OK. I'll take a minor stab at this. First, these bikes, while rated at 130 ish HP, that's a crank measurement and should make about 110 to 115 rear wheel HP. That being said, I believe some of the Euro models were in fact restricted and limited to 100 crank HP, or about 88 RWHP. When Shadow shows up, he might have more info on this. There aren't a lot of European members on this board, outside of the UK, so knowledge as to whether you can and/or how to de-restrict might be limited. Second, I would think that a well running unrestricted 1000F should be quite a bit faster than your CBX750.

 

If you could post some pictures up it might help mate, not clear on what the white wedge is, unless it's just the plastic wedge that's used to hold the air filter?

I think the only restriction was in the carb rubbers?

What year bike do you have? The early bikes are slightly more powerful.

If you want some fun with acceleration, maybe you should play around with the sprockets.

But at the end of the day, she is a heavy old bike and with standard gearing she's never gonna go like a R1 or a 1000RR. She is after all a 'Sports Tourer' which is a compromise in itself. She does everything quite well, but she's not an out and out racer