Newbie owner with exhaust question

[SPEEDYMAN]

Hello all!

I am a first time Triumph owner having been a Harley guy before so I know nothing about these bikes.

I bought a 2003 Speedmaster at an auction and it is such a sweet bike I may never go back to a hog again.

I do have a problem I need some advice on. It runs great however it was idling at 2000 rpms. I adjusted it down to about 1100. After adjusting it I now have a pretty bad exhaust popping noise on deceleration and when revving it up. I dont understand how adjusting the idle made this happen- it always had a little pop before but now it is quite bad.

I don't know if the pipes are stock or not so maybe someone can watch the video and tell me.

From what I've read this may be a lean condition and if so will it cause damage and how do I correct it?

[video]http://s151.photobucket.com/user/cybrdweeb/media/TRIUMPH%20SPEEDMASTER/M4H06318_zps788982e3.mp4.html[/video]

 

[The Seeker]

Hi and welcome to TT and the best motorcycles in the world!

I am not an Speedmaster expert at all (never owned one) so I can only say that it's popping more now because it is decelerating more. Before it only decelerated down to 2000 rpm and now it is decelerating down to 1000.

I just don't know if it's a FI or carbed bike or what stock pipes look like.

Someone with more Speedy knowledge will jump in from here.



Posted with TapaTalk

 

[CarlS]

That is a nice looking bike! I really like it. Popping on deceleration is a characteristic of parallel twins. My old Triumph does it and my 2003 Bonneville does it. You are correct in thinking it is caused by a lean condition. I could correct mine by installing 42 pilot jets replacing the stock 40 jets. However, I like the popping on decel.

Since you bought this bike used and you don't have the history, you really don't know what size main jets or pilot jets the bike has. These bikes cam from the factory running on the lean side to meet EPA certification requirements. If those are not the stock pipes and more free flowing pipes were installed, the carbs should have been rejetted to compensate. Some guys with Bonnevilles, rejetted to slightly larger jets while running stock pipes to get a slightly richer mixture. My Bonneville came with 110 main jets. I installed free flowing pipes from a 60's era Triumph and removed the snorkel to increase the air flow. I ended up installing 118 mains and my air/fuel ration is almost spot on all three the throttle range.

I recommend that you put your bike on a dyno with exhaust gas analyzer and see what you have. You will get a graph read out showing you the a/f ratio, torque, and horsepower. You can rejet and fine tuen it from there if needed. It will cost you for a dyno run; but I think it is a good investment. I dynoed my Bonneville stock, dynoed it again after I changed the exhaust and intake and installed larger jets. That run showed me I was running too rich and I rejetted accordingly. The third run showed that I was nearly perfect with the a/f ratio and that my torque curve had improved.

I would rather be a tad on the rich side rather than a tad on the lean side as lean means more heat.

That said, I am not sure what the stock jetting is on the Speedmaster though the Bonneville and Speedy engines are the same.

 

[devo]

Gidday Mark
Sweet ride bud,I had an 04 the same colour scheme as that,I loved it.
The earlier ones,up to 05 had the 790 in them with more overlap on the cams, and they actually made more HP than the later 865 motors.
Anyway,your situation,and its not a major.
From the vid,you are deffinately running aftermarket pipes as they are short slash cuts,and definitely louder than stock.
It appears in the vid that you still have the air injection system in place, and this really wants to be removed as the purpose of them is to add air to any unburnt fuel entering the pipes thus causing it to ignite.The downside of this system is it will pop on decell and turn your pipes blue.
Looky here for the fix.https://www.triumphtalk.com/showthread.php/17616-Air-injection-eliminator-kit-and-How-to-re-790-and-860-twins
Then you will need to check the jetting in the carbs.On my speedy I simply increased the pilots by 1 size (btw,harley jets are the same), but on my america I went up 1 on the pilots and the mains as I am running without the snorkell as well.