2004 Yamaha Grizzly HMF Swamp Series Exhaust

[Ajmboy]

Starting a new thread on this topic. Installing an HMF Swamp series slip on. Needs to be jetted, so I took the bowl off and..stripped out the carb bowl screws, they're so damn soft. Had to leave it alone and order some screws, bowl gasket, and new air filter. Just waiting for the parts to come in.

Edited April 29, 2011 by Ajmboy

[DirtDemon]

May I suggest some socket cap allen head screws from your local hardware store? The first thing I do to any of my carbs is replace the float bowl screws. The allen head screws don't strip. BTW, that Grizz looks like it is in good shape, nice score.

[Ajmboy]

May I suggest some socket cap allen head screws from your local hardware store? The first thing I do to any of my carbs is replace the float bowl screws. The allen head screws don't strip. BTW, that Grizz looks like it is in good shape, nice score.

Thanks, that's a good idea. I ordered extra screws from some Yamaha parts site, just waiting for them to come in. I don't even know if I have a local hardware store except for a Home Depot.....

[DirtDemon]

Thanks, that's a good idea. I ordered extra screws from some Yamaha parts site, just waiting for them to come in. I don't even know if I have a local hardware store except for a Home Depot.....

Home Depot is where I got the screws for my carbs. They don't have a huge selection of metric stuff, but they did have Allen head socket cap screws that match the threads on my float bowl screws. The heads are kind of small, so it is best to use washers with them. I think they are 4mm screws with a .7 thread pitch, basically a common 4mm machine screw. If you have problems again with the new phillips screws you have coming, or you just want to upgrade anyway, I would recommend this to anyone who has to do frequent jetting changes. The allen head screws are so much easier to deal with than the phillips. I think that the persons who invented phillips and flat-head screws should be exiled to a poor war torn counrty for all the frustration they have caused me. This Allen fellow who so kindly gave us the allen head screw should have a statue built in his image.

[Ajmboy]

Home Depot is where I got the screws for my carbs. They don't have a huge selection of metric stuff, but they did have Allen head socket cap screws that match the threads on my float bowl screws. The heads are kind of small, so it is best to use washers with them. I think they are 4mm screws with a .7 thread pitch, basically a common 4mm machine screw. If you have problems again with the new phillips screws you have coming, or you just want to upgrade anyway, I would recommend this to anyone who has to do frequent jetting changes. The allen head screws are so much easier to deal with than the phillips. I think that the persons who invented phillips and flat-head screws should be exiled to a poor war torn counrty for all the frustration they have caused me. This Allen fellow who so kindly gave us the allen head screw should have a statue built in his image.

Nice, thanks for the info!

[Ajmboy]

I took your advice DD, I bought those allen head screws. I still have not got the parts by mail...

Yesterday I wrapped up the exhaust, installed a HMF Swamp series slip on. I installed a 175 main jet per recommendations from HMF. Starts right up, but I noticed some smoking going on. I changed the oil, because it was due and black. Seemed to get a little better. I'm wondering if I should go down to a 165 or 175 main jet. I also am waiting on a new air filter, stock replacement. The exhaust sounds nice.... Just a little bit of a rough idle and slight smoking. No smoking with the stock exhaust. I've never gone aftermarket exhaust, so this is new to me.

[Ajmboy]

I've installed a HMF Swamp Series slip on exhaust on my Grizzly. I noticed a bit of smoking coming from the exhaust. Jetted it to HMF suggested 175 main jet. Seems to run pretty smooth. Definately feel more power. attached some pictures. I'm going to write up a full review for QUADCRAZY.

Edited April 29, 2011 by Ajmboy

[MIKEL5469]

i have a buddy that has a brute force and he put on the same exhaust and his quad smoked a little at first,so i believe this is common with a new exhaust,and he loves the swamp series exhaust,he noticed a power difference and more mid and low end power,i think u will prolly like it,but he thinks he may have lost a little power on the top end,but then again that it where you use the most of your power.

[Ajmboy]

yeah I like it. I like the sound most of all.

Here's a before and after video;

HMF Swamp Series Yamaha Grizzly Video » QUADCRAZY ATV Community

[Ajmboy]

Here's my full review posted by QC: ATV Articles » HMF Swamp Series Slip On Exhaust Review » QUADCRAZY ATV Community