I fried a crank bearing last season, which left me with two cyliders that need replating. I realize switching out the 680 jugs with 800 xcr jugs is somewhat common. My question is will my current psi pipes (wedge body) bolt up or are the exhaust flanges angled different and will the pipes themselves clear the exhaust valves. What other B.S. would a guy encounter with this swap? Thanks!
800 ves cylinders on ultra case
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exhaust port is different, the xcr slopes down where the ultra comes straight out, xcr is a 4 bolt pattern,
with a little work you could make stock 800 xcr pipes fit.
if you get cylinders with heads and ves ass. all you need is new pistons and pipes and you are good to go.
with a little work you could make stock 800 xcr pipes fit.
if you get cylinders with heads and ves ass. all you need is new pistons and pipes and you are good to go.
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not exactly true, if you got the money for an xcr yes, but its not all that much money or work given the fact you need 2 cylinders redone anyhow, and a stock xcr exhaust shouldnt run ya much dough.
would be royally impressed with the power of an xcr8, with what ive always loved the wedge body style.
would make an excellent summer project.
just gotta weigh your options and see which route you want to take.
would be royally impressed with the power of an xcr8, with what ive always loved the wedge body style.
would make an excellent summer project.
just gotta weigh your options and see which route you want to take.
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Check out the available 800cc kits for the Ultras.
You can run your PSIs with them and make some REALLY big power.
The HTG kit is good, there are a couple others available as well.
You can run your PSIs with them and make some REALLY big power.
The HTG kit is good, there are a couple others available as well.
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The whole 800 project is a fairly easy set up, cylinders, pistons, heads, the only trouble is the pipes like Madcow stated. The angle of the exhaust port to mount the pipes. It's mainly the mag side pipe that will hit the top of the water pump.
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to make an 800 kit out of the ultra cylinders you are looking at about 230 dollars a cylinder for boring and recoating, then you will spend about 50 bucks a head for resizing and shaping them, pistons will be about the same no matter what top end you use.
to go to the xcr 800 top end its about 200-300 per good cylinder with heads and ves assembly, then you just need pistons and pipes.
no matter what way you go the power difference between a piped ultra and a stock 800 xcr is very different. on paper they look like close in hp, but on the trail its day and night, the xcr top end has so much more low to midrange power.
ask some of the guys who rode the 800 xcr rmk i did, some of them siad they never thought a triple could have that much power down low.
to go to the xcr 800 top end its about 200-300 per good cylinder with heads and ves assembly, then you just need pistons and pipes.
no matter what way you go the power difference between a piped ultra and a stock 800 xcr is very different. on paper they look like close in hp, but on the trail its day and night, the xcr top end has so much more low to midrange power.
ask some of the guys who rode the 800 xcr rmk i did, some of them siad they never thought a triple could have that much power down low.
That's exactly what I'm looking for is more low end. I have battled the ultras notorious low end bog for a long time. I have tightened up the sheave clearance, played with pilot jets, drilled out the pilot bypass. These things have helped, but I think the rest lies in the clutch. I think my wieghts are too heavy, I'm running hotseat L1 (59g) medium tip weights. I think a lighter wieghts with a heavy tip may help. I am only pulling 8100 rpm, but my pipes peak @8700 rpm. I've heard a set of UFO's help the low end also.
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I'm just curious what size cut aways your running?
Edit:If your running the stock 2.0 cut aways (96 ultra sp) try going to the 3.0 cut aways off the stock 97 spx to get rid of that low end bog.
A buddy of mine has the same motor , but he kept the carbs off his xcr 600 sp trip/trip with 2.5 cuts, HUGE difference in performance between his and mine, in fact I'm going to pick up the 3.0 cuts, because I've been fighting the bog way to long.
Edit:If your running the stock 2.0 cut aways (96 ultra sp) try going to the 3.0 cut aways off the stock 97 spx to get rid of that low end bog.
A buddy of mine has the same motor , but he kept the carbs off his xcr 600 sp trip/trip with 2.5 cuts, HUGE difference in performance between his and mine, in fact I'm going to pick up the 3.0 cuts, because I've been fighting the bog way to long.
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I do not. Although the concept on what I've read about ufos seems to make sense, or should I say it looks good on paper.Tripledog said:
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