*POP* and Hesitation/Flat Spots

[Ingah]

Well that went well...

Having spent the last few days fighting with my carburettors, engine manifolds and airbox (along with masses of jubilee clips), i finally lost my patience with the bike and sent it to the garage for them to finish off the job (i.e. take the carbs off yet again) after i realised i'd trapped the choke cable in the left switchgear and the accelerator/deccelerator nipples were connected the wrong way round (so that my throttle was operating in reverse) - i'd done everything else by this stage and was/am sick of the whole shebang.

Note: My restrictor kit consisted of restricted engine manifolds and a jet change (#122 to #125 for restriction - that's bigger jets for restriction as #122s are standard, but i didn't question Honda on that point).

I picked the bike up earlier, and unfortunately found that it no longer accelerates properly! The bike is fine provided i only open the throttle part-way, and don't go above 5/6K RPM (10.5K redline) - i.e. ride it like my CG125. But with a large throttle opening and/or higher revs, it makes a noise that reminds me of the inrush of air, and accelerates quite slowly, almost hesitantly, like a big flat spot. It also makes the odd popping sound, indicating it's running lean.

I took it back immediately, and the mechanic managed to adapt a jubilee clip to fix the one that was missing between the carbs and the engine block (my fault, i'd broken it during my exertions), as he surmised this could be the problem. This didn't solve it though

I'm thinking it's an air leak somehow (air leaking in), but i did partially take the carbs apart myself whilst changing the jets, so it's very possible there's been a mistake there on my part. I'm bitterly disappointed it's not working as i tried very very hard to do it myself initially and have the skinned knuckles to prove it!

The mechanic is next available on tuesday, and i'm hoping i don't have to take it back as it could well take a while for him to troubleshoot, which will hurt my wallet even more. That and it's my main transport! It's now a little too late to have never started the job in the first place

[Petarded]

This sounds very similar to what happened to my gpx 250, it turned out the cams weren't balanced or something? Maybe this is something you could check? I dunno, just a suggestion.

[Guest]

Did he balance the carbs after he restrict it or not? This could be the problem?

[Ingah]

Did he balance the carbs after he restrict it or not? This could be the problem?

 

No i did not. And as he pretty much just took it apart to correct my cable mistake, he wouldnt've either.

The carbs were synced about 6 months ago (admittedly while still restricted), so does the process of derestricting mess up the syncronisation every time then? (It'll be quite a pain for me to check as i don't own the gauges yet and am feeling the pinch on the finances now, i've recently bought yet more tools anyway!)

[Guest]

Did he balance the carbs after he restrict it or not? This could be the problem?

 

No i did not. And as he pretty much just took it apart to correct my cable mistake, he wouldnt've either.

The carbs were synced about 6 months ago (admittedly while still restricted), so does the process of derestricting mess up the syncronisation every time then? (It'll be quite a pain for me to check as i don't own the gauges yet and am feeling the pinch on the finances now, i've recently bought yet more tools anyway!)

 

Well im no expert but have heard carbs need balancing when restricted, so im assuming would also need to be once unrestricted also.

I do believe you can do them your self for cheap, but i've never done it so need to ask the likes of WF

Hope ya get this sorted soon

[Guest]

as this seemes to have been a job carried out by two people, things may have been missed, could be you still have some form of restriction... which is making the bike run lean..

to check the carb issue, start the bike, get it running on tickover, and not choke, then spray WD40 in the carb rubber area, don't just spray the whole thing, but work systematically, if the revs climb, you have a leak, as the wd is being drawn into the engine and acting like a fuel.

[Ingah]

There wasn't an air leak.

However, i'd made 2 mistakes with the carburettor.

1) Somehow not secured the main jet on one side correctly so it had fallen out and was loose in there! (Explaining lack of top-end)

2) During my attempts to disassemble the carb, i had unscrewed a screw and found it led to nothing, so screwed it back in, tightly. This was the air/fuel mixture screw on one side of the carburettor, and explained the lean running while idling etc.

So red face for me - lighter of pocket too (as repairing my bodges at the garage cost me more than if i'd just given it them in the 1st place), but lessons have been learned