It spins quickly I believe. Do you mean the sound when you hit the ignition and it makes an electrical sound just before the engine fires?

When I had discharged the battery, it would spin slowly, I believe.

Thank you

 

If you have the kill button to stop it from firing, then press the starter button it should wizz, spin the engine over the same speed as a car being started with a decent battery etc

 

It sounds like carb issues to me. Do you know when the last time it had the carbs cleaned/rebuilt/ or even re-synchronized? with the choke in the on position, when starting it cold, you shouldn't give it any throttle. With the way the choke circuit works, opening the butterflies negates the choke circuit. If you leave the choke on too long it could also run the motor to rich and flood it out. Hard idling indicates pilot circuit issues. This could be pilot jets clogging with junk or you may need to turn in the idle adjust screw some. these bikes should idle around 1000-1200 rpm with choke off once warmed up. as the bike warms up choke should be gradually closed.

 

Yep, it seems like a air/fuel problem. Remove and Clean the carbs thoroughly. It is an easy job once you have done it a few times. Use the correct phillips screwdriver head to remove the screws (they will strip otherwise) If the bike has standard exhausts it should have standard jets & carb settings. If it has an aftermarket exhaust double check the main and pilot jet size and how many turns the airscrew is out (2.5 standard) i'm assuming you do not have pod filters. Make sure you don't have any air leaks after re-fitting (spray wd40 around the intakes and if revs pick up you have an air leak). If you are not comfortable doing the work get a quote from a decent mechanic and i bet it will be sorted out pretty easily. Good luck.

 

Thank you both for the replies, this is immensely helpful. I'm very much on my own with this. I haven't had the chance to look at it until now. Work, weather and easter. I'll try to clean the carburators (and pilot jets?) tomorrow. Would there be anything I should be aware of or change while I'm at it? Air filter or some **** somewhere? Also, am I able to do this with the tools provided from the bike? They seem very versatile.

What seems odd to me is that I was able to start it using a very large extra battery and some thick cables. It ran for two days, and then, one morning, it started and just died out again (as above). Would bogged up carburators cause this kind of behaviour? It sounds like the combustion is being strangled. This is running it idle with choke on.

When I struggled to get it started I had to give it throttle to start it. Otherwise it would just hiss and rumble.

I don't know when they've been synchronized but I would assume it hasn't been checked for 1½ year. It has aftermarket exhausts on it and I'll ask the previous owner about tuning.

Thanks

Edit:
There's a guide on here on how to balance the carburators. I think it could be useful but I'm not able to view any of the images. Would this be possible somehow?

 

First thing i'd do is get a service manual. There are so many little adjustment to watch for and to set things to that having a manual is good assurance that things go back correctly. I have the factory service manual for my 88 i'd scan pages for you, but theres a big gap between 88 and 99, and the carbs definitely changed. I'm not sure if you can get away with pulling them with the tools supplied by the bike, my guess is it would be easier with a simple metric socket set, an extension, and some screw drivers. also open end wrenches for the throttle cables.

 

Thank you!
I think I am set up. Metric sockets and multiple open-end wrenches are provided by the kit in the bike and I have a toolbox too. I know this is very rudimentary and basic but do I need some compressed air or can I clean the pilot jet and carburetors using some solvent and a cloth?

Been reading up a bit on carburetors and pilot jets and it seems the latter is very likely the culprit here. If it's clogged it'll be hard to start and difficult to keep idle - as someone suggested here earlier.

However, perhaps I should take my motorcycle to a mechanic to have the carburetors synchronized as well? What are your thoughts on this? I've read that these machines go out of synch fairly quickly.

There are service manuals on here and similar ones on the internet, would they suffice? I've had a hard time tracking down the 1999 manual (most manuals end at 1996, the end term of production in USA).

 

Q1. There are service manuals on here and similar ones on the internet, would they suffice? I've had a hard time tracking down the 1999 manual (most manuals end at 1996, the end term of production in USA).

A1. The 1999 model is the same as the 1996. The service manuals on here will be fine. I personally like to have a hard copy, so I bought a Haynes manual.

Q2. However, perhaps I should take my motorcycle to a mechanic to have the carburetors synchronized as well? What are your thoughts on this? I've read that these machines go out of synch fairly quickly.

A2. Synchronising the carbs is not difficult and does not need doing more often than any other bike, you will just need to buy some gauges to do it. They will need syncing after they have been cleaned. There is a 'How To' on carb syncing for this bike somewhere on the forum, you need to have a good read through the 'Hurricane' section of the forum here :-

https://cbrforum.com/forum/cbr-1000f-hurricane-38/

If after reading through, look for tutorials on YouTube to watch and then if you're still not confident enough to do it yourself, by all means have a competent person do it for you. I would say that goes for anything on your bike really.

Q3. I think I am set up. Metric sockets and multiple open-end wrenches are provided by the kit in the bike and I have a toolbox too. I know this is very rudimentary and basic but do I need some compressed air or can I clean the pilot jet and carburetors using some solvent and a cloth?


A3. Best to buy what you need as you go along to avoid spending out lots of money on tools you don't need. I would say a fairly basic socket set, some allen wrenches and some open ended spanners should be fine for most jobs.

Compressed air would be an advantage, but not essential.

Jets and the like, I soak in carb cleaner and blow out with air (or your breath). DO NOT CLEAN WITH A CLOTH! You'll undo all your good work.

Work on one carb at a time so as not to get the parts mixed up.

 

So, I've been trying to remove the Carburetors today but I've run into a problem.

I simply can't wiggle it off the point where it mounts to the engine.

I tried prying it off using a piece of wood and it'll wiggle a little bit but it won't come off. I'm using quite a lot of force.

I've disconnected the Air box and pulled it a few centimeters back so there is a gap between it and the carburetor. I just can't get it off the engine! Any ideas? I tried spraying some WD40 around the mount but stopped thinking it might be a bad idea? I've got some vaseline as well but there is only a very narrow crevasse.

To be sure, there are only one clamp on each "boot" that holds the carburetor onto the engine right? Further towards the engine I see another clamp, but it is impossible to access with the carburetor mounted in place.

It's the exact same problem as this guy:
https://cbrforum.com/forum/cbr-1000f...-1000f-138537/

I've used the tips in the thread, still can't get it off.

Here is a picture of how I try to pry it off. I've tried putting the woodpiece underneath the Carb as well. Still only wiggles.



Here are the set of (top) clamps holding the Carburetor onto the engine:



However, underneath and closest to the engine is another set of clamps. They do not look like they've been handled in a long time. I've been able to release two of them, but the two middle ones are completely impossible to get to.



I'll try to wiggle it some more in a bit. Unfortunately it'll rain this evening and tomorrow so I was hoping to have the Carb off and getting it cleaned meanwhile.

Many Thanks!

 

Each boot has two clamps. You only need to loosen the lower one on each boot.
Using a hair dryer helps. Apply the heat to the boots to soften them up a bit. Rock them forward and backwords as they get warm.
After all these years they will be stuck pretty good but don't give up, they will come off eventually.
Now is also a good time to replace them with new ones.