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  • KD7GLO
    replied
    Originally Posted by rpcraft View Post
    You need to get a new one and should if you do not have a willingness to rejet but if you are still running the stock air filter then you are probably due for having the carbs cleaned and serviced as well. If going to that extent why not get a jet and filter kit from JD at hordpower.com and free yourself up some extra horsepower. The upside is the filters you get from him are serviceable
    Thanks for the advice I appreciate it!

    Leave a comment:


  • rpcraft
    replied
    You need to get a new one and should if you do not have a willingness to rejet but if you are still running the stock air filter then you are probably due for having the carbs cleaned and serviced as well. If going to that extent why not get a jet and filter kit from JD at hordpower.com and free yourself up some extra horsepower. The upside is the filters you get from him are serviceable

    Leave a comment:


  • KD7GLO
    replied
    Not sure if this is the correct place for this question, if not I am sure I will be informed by you guys.

    Here's the question: my air filter looks ok and I cleared it as best as I could, but the bike has almost 70k and it's probably the original, should I get a new one?

    Thanks

    Leave a comment:


  • kiwi
    replied
    Originally Posted by RichardC
    Thanks once again for all the help.

    Has anyone got any experience with regard to running a Canadian 88 Hawk on the 95 octane petrol (that's 'gas' to you colonials I suppose! hehe) we have here in the UK? Don't you run on lower octane fuels 'over there'?

    While I've got my carbs in bits, I could take the opportunity to adjust/replace the jets - does the octane ratio make a difference?

    btw:

    http://homepage.eircom.net/~hondabros/index.html

    and carbs info:

    http://homepage.eircom.net/~hondabro..._OVERHAUL.html
    I run my bros 400 on 91 octane (unleaded)

    Leave a comment:


  • RichardC
    replied
    I've hm'ed and ha'd about this for a while as I really don't feel like pulling the carbs apart to find that my mechanical skills aren't up to putting them together again (and let's face it' they can be a pain in the ass sometimes).

    So: I tried this dutch fuel additive which is supposed to clean the deposits made by unleaded fuel, and it's worked a treat! No more coughing and misfire (fuel starvation) from the front cylinder at all after blatting along at 90 or so.

    I can't remember what it's called but it cost 6.99 for a bottle which will treat 40 litres of fuel.

    Leave a comment:


  • RichardC
    replied
    I think I've found the problem, and it's so simple...

    I've had problems getting the airbox top off as one of the screw heads was mashed - I'm told they make them out of Japanese cheese?

    Anyway, I got round to drilling it out today. No problem there any more.

    However, I'd been replacing the airbox without seating the carb 'boots' properly, as it's almost impossible to get to them from underneath. This had resulted in the front carb 'boot' not forming a proper seal. I tried this with the air filter removed and sure enough, the back 'boot' would seal OK but not the front.

    I'd imagine that, at speed, the boot would then suck 'false' air from around the edge of the boot.

    The problem no longer appears now I've seated them correctly.

    I can imagine that the greater volume of air would lean the mixture: but would it maybe empty the float chamber as well?

    Thanks for the many tips anyway.

    Leave a comment:


  • RichardC
    replied
    Thanks once again for all the help.

    Has anyone got any experience with regard to running a Canadian 88 Hawk on the 95 octane petrol (that's 'gas' to you colonials I suppose! hehe) we have here in the UK? Don't you run on lower octane fuels 'over there'?

    While I've got my carbs in bits, I could take the opportunity to adjust/replace the jets - does the octane ratio make a difference?

    btw:

    http://homepage.eircom.net/~hondabros/index.html

    and carbs info:

    http://homepage.eircom.net/~hondabro..._OVERHAUL.html

    Leave a comment:


  • JR
    replied
    Here is a picture I found with the airbox cut:-
    http://home.comcast.net/~hondahawkgt...010002copy.jpg

    Leave a comment:


  • JR
    replied
    Check also if the float valve (little spring loaded plunger that touches the float tap) has not seized.

    Leave a comment:


  • brewsy
    replied
    I haven't got any experience of those things Rich.
    I would recommend getting a gasket kit though.
    They are all rubber and after near 20 years were as tough as old boots.
    As for cleaning them you just need to use some elbow grease, some kind of solvent with a small brush. There will be crud at the bottom of the float bowl and perhaps crust around the jets.
    Pull all the jets and the float assembly out then blast compressed air through all the openings.
    You should be able to hold the jets and bits to the light and see through all the holes if not you may have to use a bit of wire and poke them out.

    HTH,
    Marc

    Leave a comment:


  • RichardC
    replied
    Oh well...it looks like a carb rebuild is the way to go.

    My guess is that it's there the problem lies: a former owner stored the bike for a while (6+ months) with fuel in the tank which has probably deposited stuff in the carbs.

    What about carb cleaners like Seafoam, Redex, etc? Anyone got any experience with these?

    Leave a comment:


  • PaullyBoy
    replied
    The other two fuel filters are inside the carbs themselves. And the only way to get to them is to pull apart your carbs. And it is located under the float valve seat. Here are the pics from the service manual. You can see the filters in the bottom pic.

    Leave a comment:


  • RichardC
    replied
    Hey, thanks for the tips, guys...this kind of information is really great.

    3 fuel filters on your Hawk. The one inline between the tank and the pump is the obvious one, each carburetor bowl has one inside, (small and easy to plug up) and the petcock dip tube has one over it as well
    I can find the one before the fuel pump, but I have no idea where the others are...got any links to drawings etc. that might show where?

    This can cause a slow trickel of fuel to reach the carbs. This will allow the bike to cruise fine at part throttle, but it will stumble at full, then go back to normal again once you've gone back to part throttle.
    The symptoms make me think that the float chamber is emptying on only *one* of the carbs...it's no problem on mixed roads (like the twisty backroads we have here...damn they're good!), it's only on fast, even stretches with constant high speeds (75+mph).

    Cheers once again...

    Leave a comment:


  • PaullyBoy
    replied
    Also on the fuel starving problem. The petcocks themselves have a rubber seal in them that deteriorate. This can cause a slow trickel of fuel to reach the carbs. This will allow the bike to cruise fine at part throttle, but it will stumble at full, then go back to normal again once you've gone back to part throttle.

    Leave a comment:


  • NT696
    replied
    Another thought:
    If it is a fuel starvation problem, it might be one of your fuel filters plugged up. As Hord mentioned in another thred, you actually have 3 fuel filters on your Hawk. The one inline between the tank and the pump is the obvious one, each carburetor bowl has one inside, (small and easy to plug up) and the petcock dip tube has one over it as well. These other ones may be the culprit of a fuel problem.

    Leave a comment:

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