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Hey guys...Would anybody know If there would be any adverse effect on the motor If there was a 2 into 2 exhaust system that had no cat and no X pipe...Apart from the sound that Is .
 

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According to posts on this topic at other forums, and on this one, the thought is that this motor/tune needs the Xpipe or Cat in order to maintain torque levels.

I am no engineer, only regurgitating what I have read and have no real world experience with the topic.
 

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Good question. As a rule of thumb, small mods to intake or exhaust will make small negative changes to the tune. Large changes will make large negative effects to the tune. Everything from the shape of the airbox to the angle and number of bends in the exhaust pipes are coded into the tune. I talked to a master race tuner at a local race shop about a custom tune for the Bobber. He stated that outside of a tune box (which essentially tricks the ECU), he would have to wait for someone in the race world to "jailbreak" the ECU, which would be unlikely for quite some time.



More to the question of "adverse effects", the engine is going to either run very lean, or rich... and out of tune. The ECU probably won't be able to adjust to such radical changes properly, but that's a guess. You will likely lose HP and torque, probably not enough to substantially neuter the bike. Your pipes, if stainless steel, will most likely turn blue, then black fairly quickly due to excessive heat in the pipes.



This is the typical reaction to changes... I'm no expert on Triumph.
 

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We have a Thruxton R at the shop that is running the arrow straight headers and mufflers. It sounds amazing and runs pretty **** good also. Bike also has a power commander on it so able to adjust as needed.
 

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My TTR has arrows no balance pipe, 93 rwhp & sounds good.
My bobber has verex headers & goldies, 110rwhp & sounds the dogs do-dahs.
As AJ says pcv to fuel spot on.
 

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I am running a 2 into 1 with no cat or x-pipe. Dealer put on the Vance and Hines tune. I also did the 12-minute adaptive tune. Subsequently, I have added a booster plug. The bike ran great with the dealer and adaptive tune but it did have a lot of pops and backfires. After adding the booster plug, it has quieted these down almost completely (I actually kind of miss them!). It currently runs smooth as silk with absolutely no issues (I really was expecting some). As far as performance, it kinda feels like it has significantly more torque. It could just be the small ass seat I have on it! It could also be that it is finally broken in but it runs like a scalded dog!!
 

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I am running a 2 into 1 with no cat or x-pipe. Dealer put on the Vance and Hines tune. I also did the 12-minute adaptive tune. Subsequently, I have added a booster plug. The bike ran great with the dealer and adaptive tune but it did have a lot of pops and backfires. After adding the booster plug, it has quieted these down almost completely (I actually kind of miss them!). It currently runs smooth as silk with absolutely no issues (I really was expecting some). As far as performance, it kinda feels like it has significantly more torque. It could just be the small ass seat I have on it! It could also be that it is finally broken in but it runs like a scalded dog!!
It would be good to understand if it is in fact running lean or rich. I just wouldn’t be happy assuming/hoping it’s okay.... I’ve seen too many engine killed over time this way! :(
 

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It would be good to understand if it is, in fact, running lean or rich. I just wouldn’t be happy assuming/hoping it’s okay.... I’ve seen too many engine killed over time this way! :(
True. It would be nice to know exactly. The engine was running a little lean prior to the booster plug. I am presuming it is running right where it needs to be currently (by the lack of signs and symptoms of a rich or lean condition - lack of misfires, smooth idle, temperature, pipes/plug condition, etc,etc). If anything it is probably running slightly richer then the factory setup (so which engine is at more risk?). I've been into motorcycles for over 25 years. I have owned and been around a lot of customized bikes but don't seem to have the same experience of engine catastrophes. Maybe I am just been lucky!
 

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We have a Thruxton R at the shop that is running the arrow straight headers and mufflers. It sounds amazing and runs pretty **** good also. Bike also has a power commander on it so able to adjust as needed.
My TTR has arrows no balance pipe, 93 rwhp & sounds good.
My bobber has verex headers & goldies, 110rwhp & sounds the dogs do-dahs.
As AJ says pcv to fuel spot on.
I have done the spirits racing x-pipe+CAI, and Tridents (currently) with the PCV, which made a world of difference, and as of the last dyno run, I'm right around the stock advertised hp and torque at the rear wheel (76 HP & 79 ftlb) .

Trirocket is your hp gains a product of a cam? or compression increase? I seem to recall a custom cam thread with your name on it?? :smile2:
 

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I have done the spirits racing x-pipe+CAI, and Tridents (currently) with the PCV, which made a world of difference, and as of the last dyno run, I'm right around the stock advertised hp and torque at the rear wheel (76 HP & 79 ftlb) .
Trirocket is your hp gains a product of a cam? or compression increase? I seem to recall a custom cam thread with your name on it?? :smile2:
Some flow work & skim on the head dynoed at 93hp,
+ cam now 110hp
Just reworked the head some more & having another cam made, should be on the dyno in a couple of weeks 120+hp.
Gotta get it just right, so I can do the same to my speed twin when it turns up.
Les
 

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Some flow work & skim on the head dynoed at 93hp,
+ cam now 110hp
Just reworked the head some more & having another cam made, should be on the dyno in a couple of weeks 120+hp.
Gotta get it just right, so I can do the same to my speed twin when it turns up.
Les
Think when your done you could post up the spec's for us.

I for one am thinking about a cam, but there doesn't seem like there is much available for these here in Canada unless I'm just not finding them, which is entirely likely :D.

If you decide to relinquish your current cam, when the new one goes in, PM me, not sure how much of a hassle it would be to get it across the pond, but I'd be interested.
 
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