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Im getting ready to put my top end back together and I want to make sure there is no leakage anywhere. How can I ensure that? and when putting new reeds on my bike with the stock cage do I need to rejet? its a 2008 stock yz125 that seems to be jetted well after looking at the carb but I had problems with bogging so I got new reeds 

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We doing a top end or reeds? Topic to thread body. ??? 

Stock reeds being replaced are not going to matter with jetting, unless jetting was chased with bad reeds. 

Just make sure the base and cage are sealed against the case. That is where they like to leak.

 

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22 minutes ago, P84ONE said:

We doing a top end or reeds? Topic to thread body. ??? 

Stock reeds being replaced are not going to matter with jetting, unless jetting was chased with bad reeds. 

Just make sure the base and cage are sealed against the case. That is where they like to leak.

 

The bike is stock so the jets should be stock and im replacing the reeds with boyseen pro series reeds. should I rejet? and do I need to put anything on the gaskets before i put them one?

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Shouldn't need to re-jet with reed replacement. If you need it, use a little (very little) yamabond 4 on maiting surfaces. Only if it's a gasket or the rubber lip is worn. 

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Shouldn't need to re-jet with reed replacement. If you need it, use a little (very little) yamabond 4 on maiting surfaces. Only if it's a gasket or the rubber lip is worn. 

There is no place near me to buy that, is there any alternative that still works?

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The art of sealing with silicone based sealers is to use a very thin film on each side of the bonding areas. More doesn't seal better but worse (and creates a mess) 

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Use Motoseal, Yamabond, Threebond or equivalent gasoline resistant sealers only.

Regular automotive RTV will turn to mush over time just by proximity with the gasoline vapors.

 

I run Boyesen Pro-Series reeds as well ('10 YZ125) no change in jetting requirements from stock reeds.

(actually my engine run's better a tad leaner than the original specs)

 

Only when I ran Boyesen Dual-Stage Power Reeds (all fiberglass) it needed a bit of fine tuning, as suggested in their instructions.

(richer pilot, leaner main jet).  I don't recommend those reeds on a 125, for the little extra gained at the bottom, it lost quite a lot of top end.

Edited by mlatour
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15 hours ago, mlatour said:

Use Motoseal, Yamabond, Threebond or equivalent gasoline resistant sealers only.

Regular automotive RTV will turn to mush over time just by proximity with the gasoline vapors.

 

I run Boyesen Pro-Series reeds as well ('10 YZ125) no change in jetting requirements from stock reeds.

(actually my engine run's better a tad leaner than the original specs)

 

Only when I ran Boyesen Dual-Stage Power Reeds (all fiberglass) it needed a bit of fine tuning, as suggested in their instructions.

(richer pilot, leaner main jet).  I don't recommend those reeds on a 125, for the little extra gained at the bottom, it lost quite a lot of top end.

Forgot to mention read the label to make sure of that. Good catch... :thumbsup:

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