Carbs need Sync-ing again

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albran

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I've had the MAX for a few months and it already need to be synced again?
It's an 05 with a little over 7K miles on it, it had about 5.5K when I bought it (I've been out of the state all summer :( ) and needed to be synced pretty bad. RAN MUCH better after sync!!

Now a little over 1K and it's starting to make that chuff sound every once in a while when idling and idles ruff. :ummm:

It sat for 3 weeks 2 times in the last 6 months.

I'm going to sync it this weekend.

Any thoughts and suggestions will be appreciated!

Thanks
ab
 
rather than a sync problem, I think you may be suffering from one of these two:

- there's some shite in yer carbs. Perform the shotgun and peashooter methods of cleaning - you can find all that info in the carbs/tuning section here.

- you're using crap gas. A lot of stations sell 'less than 10% ethanol' that's actually a lot more diluted than they care to say. Try using different brands exclusively and see if it helps.

By all means though, do your sync again and see if it's out by a lot. If it is - some of your carb sync screws or linkages may be loose..
 
I synced this weekend see the before and after pictures.
That's all I did and it's running/idling just fine!

I didn't check the linkages so I wont know anything for a while.

The original owner had the switch that moves the VBoost RPM to 3K so I know it's been "WORKED" on.

Thanks for the link about "Shooting the Shotgun" I'll do it this winter when I check the cables/linkage.

Thanks again
ab
 

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Whats up with that C Clamp on the far right tube:ummm:

I Lost/broke it decades ago, notice the clear hoses.
I actually like the clamp it's easer to adjust :eusa_dance: but it does wear out the hose.

ab
 
Lankee, they use that to control the needle bounce. You can make a set yourself with simple tools. Personally, I like my digital setup since I never have to mess with the restrictors.

I wonder if you have weak springs in the sync screws letting them back off a bit? It is a long shot but I also wonder if the engine is still breaking in?? Though not required by the manual you may want to check the valve adjustment this winter. It will have a big effect on the sync but not cause it to change so regularly.

Sean
 
Lankee, they use that to control the needle bounce. You can make a set yourself with simple tools. Personally, I like my digital setup since I never have to mess with the restrictors.

I wonder if you have weak springs in the sync screws letting them back off a bit? It is a long shot but I also wonder if the engine is still breaking in?? Though not required by the manual you may want to check the valve adjustment this winter. It will have a big effect on the sync but not cause it to change so regularly.

Sean

They make a lot of noise for a 7K motor, I'm planning to do it this winter.
10 years ago I would have already done it but I'm fat, old and lazy now.

Quick question: Do I need any SPECIAL tools to adj the valves?

Thanks for your help
ab
 
Yes, there is a compression tool to hold the buckets down so you can remove the shims. The tool isn't all that expensive (around $40). The valves normally get tighter with wear and not looser. The engine is a noisy engine anyway.

Sean
 
Yes, there is a compression tool to hold the buckets down so you can remove the shims. The tool isn't all that expensive (around $40). The valves normally get tighter with wear and not looser. The engine is a noisy engine anyway.

Sean

Does this mean you don't have to remove the cams to get to the shims?
It looks like my old (new to me in 78) XS11. I may still have the valve adjusting tool.

My 91 VFR didn't require any special tools (don't quote me on that).
BUT you had to take your measurements, remove the cams, remove the shims, check the size of the shims do a little math, go buy new shims, put it back together and hope your math was RIGHT!

Being a mediocre shade tree mechanic and a pitiful mathematician I let the Pro's do it.

ab
 
I am sure the XS is different. Doesn't it use an allen screw to push down the bucket? The tool for the Vmax rolls into place as you roll the engine over to depress both intakes or exhaust buckets at one time.

Sean
 
I am sure the XS is different. Doesn't it use an allen screw to push down the bucket? The tool for the Vmax rolls into place as you roll the engine over to depress both intakes or exhaust buckets at one time.

Sean

Wwhheeww what a trip down memory lane :ummm:. I remember 2 allen screws and an almost square piece of metal with a point. The 2 screws held the tool in place and the point held the valve open while the cam rotated out of the way OR I may be remembering my sons old Honda Civic??? :rofl_200:

ab
 
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