Decomp Adjustment [SOLVED]

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scootermcq
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My Bike: VS1400 + VL1500
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Decomp Adjustment [SOLVED]

Post by scootermcq »

My decomp does not seem to be opening properly when I fire up the bike. I have read through the service manual and I find some of the procedure a little confusing.

Can anyone walk me through the procedure in a little bit plainer English than the shop manual lays it out?
Scott

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WintrSol
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Re: Decomp Adjustment

Post by WintrSol »

Having helped a friend adjust his, I understand your difficulty with the manual; interpreting it took a lot of thought, while examining the engine. Unfortunately, it's been over a year, and I don't have a copy of the service manual to refresh with, or I could help walk you through it. Got a link to one?
Florissant, MO
CB450K3, GL1500CTValkyrie

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scootermcq
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Re: Decomp Adjustment

Post by scootermcq »

I do have a manual.... which I reread about 5 times and it is sinking in.

I also found info a Mocs place which makes it much easier than the manual way. It's interesting that it is so different adjusting the decomp on a 1500 vs 1400
Scott

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scootermcq
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Re: Decomp Adjustment

Post by scootermcq »

Just as an update if anyone is following this thread. I found an easy way to do it, rather than open up the crankcase to spin the piston to TDC and have to replace gaskets and go to all that work.

While the bike is idling, push the decomp lever with your finger. You can feel it being "bumped" and then just lower it a wee bit so it is not making contact when TDC. Remove the slack from the cable and Bob's your Uncle, it's adjusted.
Scott

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stillrolling
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Re: Decomp Adjustment [SOLVED]

Post by stillrolling »

Is there a danger of going to far to get "bumped" and possibly doing damage. Bad luck seems to follow me and I'd hate to have to put new pistons in again........ Like when I dropped a carb screw in the front cylinder.....I found it when I started it....ugh.

Forge
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Re: Decomp Adjustment [SOLVED]

Post by Forge »

stillrolling wrote:Is there a danger of going to far to get "bumped" and possibly doing damage. Bad luck seems to follow me and I'd hate to have to put new pistons in again........ Like when I dropped a carb screw in the front cylinder.....I found it when I started it....ugh.
Holy crap. What a nightmare!
Arthritis sucks!

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WintrSol
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Re: Decomp Adjustment [SOLVED]

Post by WintrSol »

stillrolling wrote:Is there a danger of going to far to get "bumped" and possibly doing damage. Bad luck seems to follow me and I'd hate to have to put new pistons in again........ Like when I dropped a carb screw in the front cylinder.....I found it when I started it....ugh.
I think the decomp mechanism provides a fixed amount of lift, so shouldn't interfere with the pistons. The adjustments just get it to the point where it is properly activated and deactivated.
Florissant, MO
CB450K3, GL1500CTValkyrie

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