Could this be causing bogging in midrange?

[Mike]

Finally got the bike back together, so I took it out for a bit tonight. At about 5k, it starts to bog pretty bad. At about 1/4 throttle, it can sometimes push through it, but it was struggling to hit 55. I didn't bother tightening up the clamps on the airbox boots because the screws are stripped and I'm going to get new ones. The airbox is seated on the carbs good, but it's not tightened up.

Could that be causing the stumbling, or do I need to be looking for something else?

[sachsaca]

I'm no expert here but from what I've read here you should have everything buttoned up tight before you try other things. You'll have too many variables. Get the clamps first then go from there.

[chef1366]

Get the airbox sealed up and check the petcock.

[Gssheller]

This sounds very similar to the power problem I had without any weather stripping on my air box at all. Once sealed, ran great!
Seal it up and go!
Or at least eliminate that as a potential problem!
Good luck

[Mike]

This sounds very similar to the power problem I had without any weather stripping on my air box at all. Once sealed, ran great!
Seal it up and go!
Or at least eliminate that as a potential problem!
Good luck

Awesome! That gives me some hope that it's a $3, 5 minute fix instead of messing with the carbs

[Mike]

Ok, put new screws on the clamps and it still bogs in midrange. I did notice that if it's bogging and I put the choke on, it picks right up, but then the idle hangs up if I pull the clutch in.

[Graham]

Sounds lean on the needle jets. An air leak from the air box can mimic this as well as an aftermarket air filter. That’s if you carbs are truly clean. You could raise the jet needles and/or check your air box and filter.

Just posted this on another tread.

[Mike]

Sounds lean on the needle jets. An air leak from the air box can mimic this as well as an aftermarket air filter. That’s if you carbs are truly clean. You could raise the jet needles and/or check your air box and filter.

Just posted this on another tread.

Can they be raised on these carbs? I didn't think they could, but I could very well be wrong.

[Tom R]

Assuming the 450 had CV carbs - To raise the needle you need to replace the nylon washer on top of the needle clip with a thinner washer or stack of washers.

[Mike]

Assuming the 450 had CV carbs - To raise the needle you need to replace the nylon washer on top of the needle clip with a thinner washer or stack of washers.

I'm not sure the 450 had the carbs where the needle can be adjusted. When cleaning it, I didn't see any washers around the needle, it just stuck in the body

[pete]

Hi Mike, you can definitely adjust the needles on our carbs, and I believe it's done by changing the washers in the needle assembly.

I'm a while away from doing this with mine, but I will need to do it in a month or three.

Apparently Radio Shack sells suitable nylon washers, so have a look on BassCliff's site for "shimming the needle".

What we can't do is a get a Dynojet stage 3 kit which would solve this problem for us... you need an '83 or later to be able to use the Dynojet kit.