Trek 4500/ GP460/ 8 speed SHIFTER

[waylow]

Thanks for the advice. the reason I want to mod the dominator, is because,
1. It is not perfect out of the box to begin with and needs some help.
2. Are yours port-matched? Because, the manifold on MY dominator, is WAY smaller than the exhaust port on the engine. So, one mod I want to do, is cut off the manifold end of the dominator. and mate it to the port-matched Trevor Simpson exhaust manifold that I have.

every time I look at that dom, I can hardly believe my eyes. for that much money, I expected much much higher quality. First, its alignment is all wrong, if bolted to the head, the lower pipe mounts are no where near ligned up with the bolts that hold the clutch cover on... Don't those need to line up? Other than that, the welds are ugly, the chrome stuff like didn't chrome a lot of the welds, so the welds are just rusting, and it has never been outside... (still inside my house b/c the bike isn't near finished yet) That and the whole port matched issue just blows my mind.


SOOOOO.... That is why I felt it necessary to alter my dominator.

 

[DetonatorTuning]

ok, is the diff. in the outside of your 460 port and the inside of the Dom. flange so large you couldn't simply dremel them to match ?

maybe they are, AND maybe you don't like the way you can tell the mating surface of the flange is NOT perfectly flat ? in either of these cases you might improve things by using the TS adaptor flange (is that te one you mean, the one with the short pipe stub ?)

you'll want to be careful to take the depth of the TS flange into consideration and take that much off the header pipe segment to keep the power the way it is tuned.

i know many people don't like the finish on the chrome Dom. black is where it at for me. i found the lower mount to be the same as yours. you can file the bolt holes on the mounting flange to line up and lock it down.

tuned configuration wise i really feel there is no better pipe made for this engine. but that's just me. ask kawasaki999 how he likes them, i think he's up to 3 of them now.

steve

 

[waylow]

the mounting flange is not very flat, now that you mention it. and the gasket is the same size as the port on the engine, but when I lay the gasket on the flange of the Dom, it almost looks like th...... I don't feel like explaining it, you k now the just of what I'm talking about. I am going to use the TS exhaust adapter, which matches the gaskets perfectly; instead of the stock Dom flange.
Any ideas on how to mate them? I can not weld steel to aluminum.

 

[DetonatorTuning]

is the OD of the TS stub going to slip into the Dom. headpipe ? if it will you don't ned to weld it at all. the TS flange has holes in the upper and lower horizontal webs for spring hooks.

just weld some loops onto the Dom and use springs to hold them together.

if the stub is the same OD as the Dom head pipe you're going to need to find a Fab. shop with a real good TIG welder.

 

[Gen3Benz]

I have been reading this thread too much and have compiled a parts list to build a copy...let me know if I have missed anything...

gp460 w/ .005" base gasket and custom expansion chamber

TheScooterGuy---
frame engine mount plate
5:1 reduction tranny
11T output gear.

Kings sales and service (Andyinchville)---
22T pedal drive sprocket

SickBikeParts---
sbp-fw023 crank freewheel
sbp-cs023 pedal cranks
sbp-cro44 44T chainring
sbp-fwcg024 44T chainring outer guard

KMC Z72 1/2 x 3/32 chain driving a shimano HG cluster and DEORE derailer
KMC K710 1/2 x 1/8 engine to freewheel crank

custom rear sprocket cassette 34-30-26-22-21-20-18-16
custom lower engine mount bracket

 

[thescooterguy]

did you ride today ?

 

[waylow]

Thanks for the info DetonatorTuning. I like the spring Idea.

 

[DetonatorTuning]

did you ride today ?

NO,

i had a new 59FT. mounted crane waiting for me when i went in at 6:00am.

so, in the dark, i needed to go over it, find the peculiarities, train 2 operators on it, have it loaded and on the road by 8:00am.

THEN, i needed to get ready for a full DOT audit of my operator, vehicle and service records at 1:00pm.

that was MORE than enough for me.

 

[DetonatorTuning]

I have been reading this thread too much and have compiled a parts list to build a copy...let me know if I have missed anything...

gp460 w/ .005" base gasket and custom expansion chamber

TheScooterGuy---
frame engine mount plate
5:1 reduction tranny
11T output gear.

Kings sales and service (Andyinchville)---
22T pedal drive sprocket

SickBikeParts---
sbp-fw023 crank freewheel
sbp-cs023 pedal cranks
sbp-cro44 44T chainring
sbp-fwcg024 44T chainring outer guard

KMC Z72 1/2 x 3/32 chain driving a shimano HG cluster and DEORE derailer
KMC K710 1/2 x 1/8 engine to freewheel crank

custom rear sprocket cassette 34-30-26-22-21-20-18-16
custom lower engine mount bracket

it's an honor that you have the confidence to consider doing this before i have an extended viability report posted.

as to the engine you will want to follow the standard breakin recommendation before you start doing mod's.

be sure to tell Andy you want a 22T chainring for 1/2 x 3/32 chain on a SBP crank freewheel.

as to the rear derailer you can use ANY one you want, just be sure it has mega-range compatability to work with the 34T cog.

depending on the bike you start with you may need to change the bottom bracket to get the outer chain ring into the correct plain for chainline up to the engine. i'm using a shimano 73 x122 cassette BB. it really depends on what frame and mounting plate orientation you're going to use.

good luck,

steve

 

[duivendyk]

Sleek Spandex's the way to go,but leather&gloves would be safer.These tuned GP 460's must be good for 6 hp or so at 13k.I wonder what speed would be attainable with low-drag fairing.The right place to find out would be at Bonneville.