Who did your engine work and how much?

[MtnEX]

For those of you who didn't do the internal work yourself... where did you take it or send it?.... (Like somewhere I could send my engine)

What did you have done and what did it set you back.

I'm trying to get an idea of what a build would cost me (thinking more than I want). I'm looking at doing a CRF450 cam chain and related parts, and while that's being done.... cylinder and head service....

Whatever is needed...
Bore/hone & 416 kit
Maybe port/polish, valves etc, stage 1 hotcam
Check bottom end/crank

[fauxamish]

I took my cylinder to GT Thunder because they are 5 minutes from my dad's house. It was $75 for the bore and hone. Labor for complete engine is $295, but I did it myself.

Taking the engine apart is not overly difficult, you just need to take your time.

[MtnEX]

Lucky you have a local place like that.


I knew about GT Thunder but I didn't know they did engines.



I could do all the work but the machining, but I don't have a place to do a teardown/rebuild anymore.

[jcs003]

four stroke tech(FST). they are innovative and reasonable.

[MtnEX]

Originally posted by jcs003
four stroke tech(FST). they are innovative and reasonable.

I've read Mikey's stuff here and would agree.
I just didn't realize they might be reasonably priced.

[dunatic]

CG Performance


I wanna say $300 for teardown/rebuild

I spent $1000 and got:

flowed head
new valves
new guides
new springs
valve grind
cylinder honed
new piston
gaskets
seals
bearings
2-3 new tranny gears

[jcs003]

mickey dunlap uses a flow bench for the port work, which alot of shops do not.

[onegtalon]

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[NacsMXer]

Messed up my previous 440 motor...overheated, bent valves, etc. Knew it would need machine work and wanted to upgrade to a stroker so I sent the entire motor to GT Thunder instead of doing the work myself/having machine work done.

Ended up doing a complete motor overhaul including:

- Complete motor/transmission disassembly and inspection
- Full race port/polish on the head
- Install +1mm OS intake valves, new guides, seals, springs, retainers, perform 3 angle valve job
- New OEM Honda rocker arms
- HRC cam
- Found out the cylinder had been warped, so got a brand new OEM jug from Honda
- Bore/hone jug out to 87mm
- GT Thunder 452 stroker kit: custom short skirt 87mm 12.5:1 JE piston, HD stroker rod, relocate crank pin out +7mm over stock, hardweld, true, and balance crank, machine the lower part of engine cases to clear longer crank throw
- CRF450 timing chain
- Hinson clutch basket, inner hub, and pressure plate
- HD clutch springs, and 8 plate clutch (8 OEM Honda 250R fibers/7 steels)

Grand total parts/labor ~$2900

Expensive yes, but it was totally worth it to me. Made my old 400 a completely different machine. Definitely recommend GT Thunder for motor work, they have competitive pricing and a very fast turn around time.

[MtnEX]

$2900 is a lot of beans to put into rebuilding a quad.



That's the downside to quads, you can sink more into mods than they are worth TOTAL very easily. That's why I was considering a new or garage queen 400EX. I could just swap my mods on and sell the old one.

I'm weighing rather or not I'd be happy with that although it's a good idea.

[NacsMXer]

Originally posted by MtnEX
$2900 is a lot of beans to put into rebuilding a quad.



That's the downside to quads, you can sink more into mods than they are worth TOTAL very easily. That's why I was considering a new or garage queen 400EX. I could just swap my mods on and sell the old one.

I'm weighing rather or not I'd be happy with that although it's a good idea.

Yea it is a lot but I did compare my options before I made the decision. It was do this, make my quad competitive with the newer 450 quads, or buy a new 450 and start all over with the modding. Didn't feel like starting over with a 450 and having to redo what I already did with the 400 all over again. That would be like $6000+ for the new quad plus several thousand more to get me to be where I already was at with the 400EX. Plus I just don't like any of the newer 450's as much as the 400EX personally anyways. $2900 was much cheaper in the long run for me.

Quads are a poor investment anyhow. We mod them to perform better, not to increase the resale value....though it does help very slightly.

The type of work you want to have done is very simple and will net you some nice increases in power for what you pay. I say go for it.

this is off gt thunder's website.... Im assuming this is for parts/labor and turning your 400 into a 450 stroker.
Anybody sent theres off and got a 416 or 426?

400EX / 450 Stroker

Basic kit:

Engine labor, machining, gaskets, stroke crank, custom 87mm piston with relocated wrist pin hole, for the extra stroke, camshaft.
$1500.00

Deluxe kit:

Basic kit, Full race exhaust, CDI, Race porting, and 8 plate clutch kit.

$3000.00

[LeGaCyGiAnT124]

$500 for the whole rebuild and hone. I got a hotcam stage 2 as well and a JE 416 kit, new timing chain, and a new clutch for that much. My buddy Wayne basically did it for free!