[shadow-rider1]

I'm going to order my pipes tomorrow (shop was closed today)
I'm thinking of buying a dynojet kit, but how do I know what jets to
go with? is it a trial and error? i eemailed road house, they replyed
back that I souldnt have to rejet....

What have others done when rejetting for the roadhouse 2into1 pipes?

 

[Guest]

i emailed road house, they replied
back that I shouldnt have to rejet....

If that's the case, go with a Dynojet Stage 1 kit and jet for stock exhaust. You'll see considerable improvement with the Stage 1 jetting over stock. Despite what they say, I'd rejet.

Here's the Dynojet instruction manual for your bike:
http://www.dynojet.com/pdf/1186.pdf

You know Tony Price? I think he lives in Katy.

 

[bocco]

I've been considering rejetting too. I have a shadow spirit 1100 and have a set of roadhouse 2 to 1 sitting in the garage waiting for a warm day. I don't think there is a bigger controversy over stock jetting vs re-jetting. I looked at the graph dynobob mentioned and it doesn't really show any gain until after 50 mph and at 80 it's only a 5 hp gain. Perhaps there'd be more with one of the aftermarket air filters. My plan is to put the pipes on and see how it rides. My goal is to make a little noise, and hopefully gain a little performance. My bike is quiter than a car. I even surprise people walking in my neighborhood as I ride past them. Let us know how the pipes work out for you.

Thanks, Bocco

 

[rickbb]

The pipe makers say you don't need to rejet because it helps sell more pipes.

Your bike will run ok without re-jetting, BUT it's like a tune up, runs better with one.

 

[shadow-rider1]

If that's the case, go with a Dynojet Stage 1 kit and jet for stock exhaust. You'll see considerable improvement with the Stage 1 jetting over stock. Despite what they say, I'd rejet.

You know Tony Price? I think he lives in Katy.

From dynojets web site:
4. Remove the stock main jets and replace with the Dynojet main jets provided. If running the stock exhaust
use the DJ165 main jet in the front cylinder and the DJ170 main jet in the rear cylinder. When running an
aftermarket exhaust with high flow baffles use the DJ170 main jet in the front cylinder and the DJ175 main jet in
the rear cylinder. Be sure that the jet you are changing is the main jet

Is the Roadhouse 2into1 system considered an "aftermarket with highflow baffels"?

Sory never heard of Tony Price, Is he on this board? might have to get together if so...

 

[rickbb]

High flow usually means LOUD no baffles at all, but there is no standard. Trial and error I'm afraid.

2 into 1's usually are not as loud as shot guns, and other str8 pipes, etc.

 

[Guest]

Is the Roadhouse 2into1 system considered an "aftermarket with highflow baffels"?

Sorry never heard of Tony Price, Is he on this board? might have to get together if so...

Well if Roadhouse say's rejetting isn't necessary, then they flow and have backpressure nearer to stock pipes. You will see a noticable difference across the powerband with a Stage 1 rejet. The bikes are really too lean as they come from the factory due to EPA restrictions. Go with their recommendations for stock exhaust for baseline and it should work pretty well.

The Roadhouse 2 into 1s will flow more than stock pipes and this will make your already lean jetting leaner.

TP is a friend who's into vintage dirtbikes. I don't think he has a streetbike. I just figured Katy was a small place and you might know of him.

 

[Guest]

I looked at the graph dynobob mentioned and it doesn't really show any gain until after 50 mph and at 80 it's only a 5 hp gain.

That really depends quite a bit on what pipes they were using for their dyno run. Dragpipes would only show gains at the higher rpms. The Roadhouse 2 into 1 would show gains (horsepower and torque) at lower rpms too.

You think a 5 horsepower gain is insignificant? Remember these bikes only have 35 or 40 horsepower. That's a 14% gain if I did my math correctly.

Your bike will run better in every way with a rejet.

 

[bocco]

DynoBob... you did the math correctly. It does make more sense when you look at it as a percent. I'm curious if anyone knows why they recommend a different jet for the front and rear carb. When I pulled my plugs out in the summer, the front plugs were a slightly different color than the back. I asked a Honda mechanic about this and he told me this is normal, and the way it SHOULD be? But will putting different jets in front and back take care of this?

One of the reasons I want to avoid the rejetting, is that when I bought a new Harley a few years back, I had the stage 1 jet kit put in by the dealer. I had a plug fouling problem for a long time. Finally the right mechanic said that it was just the opposite of what I thought. The bike was too lean. He put in larger jets and the problems went away. Both the plug fouling and the backfiring on decel. But a ton of tinkering went on to get it right.

 

[Guest]

I'm curious if anyone knows why they recommend a different jet for the front and rear carb.

It's because even watercooled Hondas get more cooling on the front cylinder than the back. The difference in cooling between the front and rear cylinders wouldn't be nearly as great as with an aircooled bike, but it is still significant.

Dynojet's recommendations should be very very close. If you use Stage 1 jetting for a stock engine, it will be richer than stock and most certainly won't be too rich with the Roadhouse 2 into 1.

 

[razzer]

I wont argue the cooling issue mentioned about the diff. jet sizes....I am in no way an expert....but!! With all my v-twin atv's the jetting is diff. because the length of the pipes are diff. thus requiring diff jets. My latest project had me put muzzy exhaust on my kawi v-twin 700 atv...sounds great and with these ther pipes are equall lebth and require same or very close jetting.

That being said, may I ask a ? now too?? am I to understand that stock jetting is 165/170? Or does DJH use a diff jet #ing system...thx

 

[Guest]

That being said, may I ask a ? now too?? am I to understand that stock jetting is 165/170? Or does DJH use a diff jet #ing system...thx

Dynojet has their own numbering system.