Got my 780cc big bore kit..now what??!!

So, finally after 2 months of waiting my 780cc bigbore kit arrived form procycle...now comes the the hard part..the install, but I'm getting cold feet as ive never done this type of work before and was hoping for some tips and words of wisdom form the group to get this project pointed in the right direction. Im not a complete novice when it comes to wrenching ive done all my work so far.

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I am green with envy. Post up a before and after video on youtube. :thumbsup: Do you have a different carb on it yet?

I am green with envy. Post up a before and after video on youtube. :thumbsup: Do you have a different carb on it yet?

Already installed a FCR41 from Sudco in anticipation..

BTW look at this thing:bonk::thumbsup:

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I sent my engine out to Eddie Sisneros in Colorado and had him port the head and install the 725 piston kit. I would recommend him and you'll have a solid engine when you get it back. Eddie is an expert engine builder who is active in the DRZ400 section.

One more thing. Can you dyno it before and after on the same dyno?

Get your manual and start pulling that thing apart. Take your time, if you need to label or mark parts for reference during assembly, do so. I'm not sure, but you may need to have a sleeve installed in the cylinder. Find a good machine shop. The people at procycle are cool to deal with. I had questions on revalving my shock, talked to Jeff on the phone and he got me me straightened out on the shim stacking. If you have questions don't be afraid to call them. I'm envious also. You're gonna have a bad ass DR!

Already installed a FCR41 from Sudco in anticipation..

BTW look at this thing:bonk::thumbsup:

DSC_0045.jpg

Holy crap that frigging thing is like a small frisbee! Definately get us some action/sound shots once your put it all together...................

Get your manual and start pulling that thing apart. Take your time, if you need to label or mark parts for reference during assembly, do so. I'm not sure, but you may need to have a sleeve installed in the cylinder. Find a good machine shop. The people at procycle are cool to deal with. I had questions on revalving my shock, talked to Jeff on the phone and he got me me straightened out on the shim stacking. If you have questions don't be afraid to call them. I'm envious also. You're gonna have a bad ass DR!

Thanks!

I already sent an extra cylinder to procycle and they took care of the re-sleeving..its all there and ready to go

Looking forward to reading about the results. Good luck!

The only advice i can give you is; check that the ring end gap has been checked by the vendor (or do it yourself) and, insure that you have clearance between the top of the piston and the valves when the engine rotates if you have an after market, high lift cam. Take your time, make notes, and take pictures if you need to (as jonboat mentioned above).

Why did it take two months? (Just curious).

This will be fun to keep up with.:thumbsup:

The only advice i can give you is; check that the ring end gap has been checked by the vendor (or do it yourself)...

+1 on this, when I installed the 725 kit I checked the ring end gap and it was half of what CP recommended in their specs, so had to have the rings filed.

I'm just pissed that a week after I installed my 725 kit ProCycle released the 780, I should have waited!

I also had a spare cylinder to have sleeved, just a matter of swapping it over with minimal down time as it's my daily rider. Best way to do it I reckon.

Try and have a spare set of hands when sliding the cylinder onto the piston. Took me like 20 minutes to get the rings compressed cause the cylinder is way heavier than other's I've worked with and it was hard to hold the cylinder and compress the rings by hand at the same time, all while the cylinder is pivoting forward & backward on the piston.

The only advice i can give you is; check that the ring end gap has been checked by the vendor (or do it yourself) and, insure that you have clearance between the top of the piston and the valves when the engine rotates if you have an after market, high lift cam. Take your time, make notes, and take pictures if you need to (as jonboat mentioned above).

Why did it take two months? (Just curious).

I was told that the reason it took so long is because these pistons are ordered in small batches, and i placed my order just after the first batch was sold out so i had to wait for the new batch to arrive.. I cant wait to get this thing installed, its tough to imagine how hard this thing is going to pull:banana:

Try and have a spare set of hands when sliding the cylinder onto the piston. Took me like 20 minutes to get the rings compressed cause the cylinder is way heavier than other's I've worked with and it was hard to hold the cylinder and compress the rings by hand at the same time, all while the cylinder is pivoting forward & backward on the piston.

good tip.. thanks

I was told that the reason it took so long is because these pistons are ordered in small batches, and i placed my order just after the first batch was sold out so i had to wait for the new batch to arrive.. I cant wait to get this thing installed, its tough to imagine how hard this thing is going to pull:banana:

Like a bulldozer I'm sure... I rode and dyno tested the 725cc version. What a friggin tractor that thing was. I'm sure the 780 is going to be stupid powerful right off of idle. :thumbsup:

Rob, now that FI is running properly - what are the next stages? I simply cannot imagine you to just ride that bike:ride: Only annoying thing for you must be the simple accesss to the procycle-kit; nothing to investigate or invent ...

Put the knobby tyres back on it! Sheeesh!

Already installed a FCR41 from Sudco in anticipation..

BTW look at this thing:bonk::thumbsup:

DSC_0045.jpg

now this dr is going to be a true thumper! awesome, love your work bro.

Rob, now that FI is running properly - what are the next stages? I simply cannot imagine you to just ride that bike:ride: Only annoying thing for you must be the simple accesss to the procycle-kit; nothing to investigate or invent ...

Actually I'm not happy with the FI bike just yet. It runs great but I want to simplify it a bit. I have a small wiring issue with it right now. Just being away from it over the winter there have been some new firmware developments that may allow me to run full sequential without having to get my cam sensor working.... then a new Microsquirt is also about to be released that looks like it will take care of the cam sensor not working issue anyway. The new input is said to work with any type of crank/cam position input sensor. The current unit is a bit fussy and took some electronics experimentation to get working. In addition the new unit is smaller, much easier to make fully water proof and costs less. I can see a big reduction in the wiring loom complexity with this new unit. I'm sure I'll be upgrading when they get released. That's how it goes for me. I'm always neck deep in something while the simple "doable in one weekend" type projects sit on the bench collecting dust. LOL!

And yes, I have every intention of putting Jeff's 830cc kit on my bike. :thumbsup:

There, that should keep him busy for awhile. :confused:

Edited by mx_rob

Dont know if i'm in the right place, its my first time , I found this bike at a dump a while a go,its a Sp 400 that needs a lot TLC , but I have just got it running , I know nothing about the bike, the only markings are the engine number 100263 and chassie 100262,

Sorry if i'm in the wrong place , please can any one help me with some info about the bike

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