416 vs 426 10:1 vs 11:1 Dilemna E-start

I'm still in the process of coverting my '96 XR4 to E-start utilizing 400EX parts. I have done the crank and wiring procedures. I have searched this issue for the past hour and still remain undecided between the 416 vs 426 and 10:1 vs 11:1 compression ratio. I have done Gordon's mods, 160/60 jets, Stage 1 Hotcam, HRC needle, UNI filter, DG exhaust. I am leaning towards the 416 with 11:1. From what i've read there might be some reliability issues with the 426 such as more heat, wear and tear, octane issues, etc... 440 is out of the question. Thanks!

I hear you loud and clear!

I had my motor built and in the frame, 426, stage 2, kibble white valves, hot rods rod kit, edelbrock, fmf power bomb, ricky stator, what am I missing?

I kicked that mule about 10 times.

Turned the fuel off and fired up the laptop, clicked on ebay and bid/won a 2005 TRX400EX complete bottom end for $390.00 shipped to my house.

When the EX bottom end arrived I tore that puupy down, yanked the crank and shipped it to Mr. Crankshaft in Ky for a new rod and some massaging.

Tonight I finished polishing the center cases that Mr Sbabs gave me, Saturday I will start on the side covers and starter.

Next week when my crank arrives I will start assembling the motor.

I am getting to old to kick start a bike, give me the happy button!

FYI, I will have a brand spanking newly built XR4 Crank with Hot Rods kit installed for sale along with a 200 watt ricky stator.

If anyone is interested shoot me a pm, also I have a couple sets of center cases and XR4 Stator cover.

For what it is worth to your decision................

One of the XR4's in our collection was purchased from a seller who had rebuilt the engine with the EX crank and starter assembly. He gave us all the receipts at the time of sale.

The paper work shows he purchased a JE Piston Kit XR/TRX 400 87.00mm 10.8/1 and he stated that was a 415 kit. He futher stated that the bike has a Stage One "Hot Cam" and a Mikuni pumper carb.

The other day the brothers were all out and switching around on bikes. We had two other XR4's there with claimed 440 kits. The gearing is not consistent, but two of the brothers preferred the 415 kitted bike over the 440 kitted............?

sirr1

why is it you are not going to use the 200 watt stator in your bike?

I too am in the process of building one of my XR4 engines. After having the same concerns that you have, I decided to go with the JE 406cc 10.6:1 piston to keep my chances of blowing head gaskets to a minimum. The slightly lower compression keeps heat down and is easier to find suitable fuel. Just got my crank rebuilt with the falcon knife rod, kibble white stainless valves and springs, port/polish, mikuni pumper, and I am either going with the web cam or hot cam stage-1. Like you, I am trying to keep most of the XR reliablity.:confused: Anybody out there have experience with a 440 kit that has been reliable/no issues for 4000 or 5000 miles?

When I built my motor I went 435cc, that gives me two more over bores if needed. I also am concerned with gas, so I used a JE 10.5 comp. piston. Even this can ping sometimes if hot or I lug the motor. In my last motor I had a Hot Rod break and it destroyed the whole motor, so this time I'm useing a Falcon Rod. I ported the head and did a three angle valve job instead of changing the cam, to keep the valve train stock. With a pumper carb, pipe and opened up the intake this motor runs real strong. I think it will last along tine

I hear you loud and clear!

I had my motor built and in the frame, 426, stage 2, kibble white valves, hot rods rod kit, edelbrock, fmf power bomb, ricky stator, what am I missing?

I kicked that mule about 10 times.

Turned the fuel off and fired up the laptop, clicked on ebay and bid/won a 2005 TRX400EX complete bottom end for $390.00 shipped to my house.

When the EX bottom end arrived I tore that puupy down, yanked the crank and shipped it to Mr. Crankshaft in Ky for a new rod and some massaging.

Tonight I finished polishing the center cases that Mr Sbabs gave me, Saturday I will start on the side covers and starter.

Next week when my crank arrives I will start assembling the motor.

I am getting to old to kick start a bike, give me the happy button!

FYI, I will have a brand spanking newly built XR4 Crank with Hot Rods kit installed for sale along with a 200 watt ricky stator.

If anyone is interested shoot me a pm, also I have a couple sets of center cases and XR4 Stator cover.

I get first dibs on the stator!

I get first dibs on the stator!

NOW NOW ARE WE BEING GREEDY?

I really am interested as to why sirr! is not using the 200w stator with the EX crank

the EX stator produces less wattage?

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