- Location
- Loveland, Colorado
What are your plans for mods?
650/X-2 winter build 650/750
- Thread starter dbattersby20
- Start date
Vumad
Super Hero, with a cape!
- Location
- St. Pete, FL
How can you say the crank doesn't have any play in it if you haven't gotten the clyinders off? If there's rust on everything, you should strongly consider replacing the crank even if it doesn't have play. The rust on the bearings could make them fail and take out your otherwise new motor. SBT it, rebuilt it right or plan on doing it again.
- Location
- San diego
The small pin has higher RPM's. Mine runs great with that single. My big pin with dual carbs runs tits too. Better lower end though with the big pin. My mechanic says to get a Intake that will adapt to a Yamaha dual carb set up. Runs way better.
- Location
- Loveland, Colorado
When you say yamaha dual carbs run way better do you just mean dual 44 or 38 sbn carbs make it run way better?
- Location
- New Jersey
I'm still guessing on the crank... I'm definitely not putting a bad crank back in. I'm just saying from what I can see there's no play, if I put my fingers into the intake I can't wiggle the shafts at all.
Are you just saying mikuni is better than keihn?
Are you just saying mikuni is better than keihn?
- Location
- Loveland, Colorado
I am not exactly sure? I was wondering the same thing. Your keilns are just fine unless you are doing a butt load of work I would say get some mikunis. My friend has a stock 98 sxi pro with a r&d head with high compression and we fine tuned dual mikuni 44's and the stock keihn's and honestly didn't feel any difference. but it is a mainly stock ski. I do perfer the mikuni over the keihn but I would put money into other parts for right now. down the road you could switch over to mikunis but I am sure vumad could give us more info on this subject.
- Location
- San diego
From what I was told the carbs off the 760 yamaha when put on a kawasaki 750 are tits. Hard tits. You have to get a diff intake though. I'm guessing it would be the 44.
- Location
- Loveland, Colorado
my friends 44's that he was running were a little ruff so A good clean set I would bet probably hit harder. jetting might had been off too.
N2 H2O
Previously Tbone550
- Location
- Charlotte, NC
Small pin 750s are ported better for low end, so it should hit harder on the low end then your big pin, but the 750 small pins came with small stock single carbs. Yamaha dual carb setups are sbn 38's. 750 Big pins came with cdkII's, which are supposed to be 38's, but are truly closer to 32mm, so the sbn38's would give a little more power. I prefer mikuni over keihin also.
- Location
- New Jersey
well i have a small pin. But someone took everything from the reeds to the carbs off a big pin i guess and put it on mine. Cause i have reeds with 12 holes and dual carbs. I might just switch to mikni 44's since i have one already... Ill see if i can trade my current set up for a 44 and the intake mani or at least sell off a few parts that i won't be using.
The stud on the cylinder block is still soaking in penetrating oil. hopefully it will be looser tomorrow.
On a side note, i ripped into the cylinder block on my seized up 650 and managed to salvage the crank and lower half of the case. Took me about 90 minutes and 50 cutting wheels on my dremel.
The stud on the cylinder block is still soaking in penetrating oil. hopefully it will be looser tomorrow.
well, I'm not really sure yet. I originally didn't think I would have to spend this much on the engine. So for now I just want to make the engine perfect. And i already have some of those handling mods in the pictures. The only thing i might do is get my flywheel lightened that way i don't need to take my engine out again during the summer. After i start working again during the summer i plan on getting an exhaust (not sure yet, i want the factory pipe for a 750, does it fit?) I'm also going to be doing things like getting rid of the fuel selector, adding in-line fuel filters, and little things like that. Also, the main mod is dropping in a 750...
On a side note, i ripped into the cylinder block on my seized up 650 and managed to salvage the crank and lower half of the case. Took me about 90 minutes and 50 cutting wheels on my dremel.
- Location
- Loveland, Colorado
yes it will fit but you either have to bubble the hull next to the head pipe or find a 650 westcoast exhaust manifold and bore it to a 46mm for proper flow. Here is a link to thread I started awhile ago on the factory pipe. Vumad makes a very good explanation in it "what needs to be done to make it fit."
http://www.x-h2o.com/threads/103959-Factory-750-pipe
- Location
- New Jersey
Yes, i know that's the case for an x2, but I have an sx...
- Location
- Loveland, Colorado
Oh sorry forgot about that. I would guess it would fit except you would have to run a 550 tank be ause the chamber might be in the way. 650sx I think are alittle wider than the 750 so it should fit minus tank. But don't know for sure!
- Location
- New Jersey
ok, i have a tank from a js300. so I can always throw that in. I just got the cylinder block off. I put a slide hammer through the spark plug hole and it came off pretty quick and relatively easily. I don't have a flywheel puller for a 750 though. Is it just one thick bolt that goes through the middle and then hits the crank?
I think I'm going to put together an order from atlanticjetsports. thinking about an ada head. What's the difference between a girdled head and regular. cause i don't think there's a price difference on their site. But you need a kit for the girdled. Im going to post back what im getting in a little bit.
edit: so I know that a girdled heat is just to support the exhaust and keep the cases from cranking. Is it worth the extra money? and how do i figure out what thickness base gasket to get?
I think I'm going to put together an order from atlanticjetsports. thinking about an ada head. What's the difference between a girdled head and regular. cause i don't think there's a price difference on their site. But you need a kit for the girdled. Im going to post back what im getting in a little bit.
edit: so I know that a girdled heat is just to support the exhaust and keep the cases from cranking. Is it worth the extra money? and how do i figure out what thickness base gasket to get?
Last edited:
- Location
- New Jersey
any advice on parts to buy is appreciated. Im going to get another mikuni 44 so where would be a good starting point for jets? i assume pop off is still at 20 or so... what flame arrestors should i get? This is my first time seeing dual carbs, so I'm not quite sure about setting them. If i run two fuel lines (one for each carb) then i can "t" the returns and all i have to do is connect the throttles? I can use single miknis....?
On the atlanticjetsports website there's a chart for what sparkplugs to buy for what jetski and i matched up the numbers from my crankcase with the chart and i think the engine is out of a super sport xi from 1993-1995.
On the atlanticjetsports website there's a chart for what sparkplugs to buy for what jetski and i matched up the numbers from my crankcase with the chart and i think the engine is out of a super sport xi from 1993-1995.
- Location
- Loveland, Colorado
On kawasaki's you don't need to weary about girdled head, regular style is just fine. There important on a yamaha.
On the dual mikunis. I would sell your one you have right now and find a set of duals. It would be alot simpler and less of a head ache. I am not sure exactly what you would want to do with jets, in my red tops I have right now, the main is 120 and pilot is 125. My needle and seats are 2.0 and my spring is 95 grams. I have not ran these yet either, just sitting on my bench. This is just what my dual 46's came with so I dont know exactly what you wound need. I live in colorado so more altitude will change it up for me. also your going to need to tap your cases for a second pop of fitting for dual carbs. You can find nice set of 44's for 100 to 130 bucks some times (good deal if they are clean!)... so I would wait for a good deal on some nice ones. You should be able to get 60 to 80 for yours depending on condition. you can always buy a second one and make it a slave carb but you just be better off get two that came from the factory together.
On the dual mikunis. I would sell your one you have right now and find a set of duals. It would be alot simpler and less of a head ache. I am not sure exactly what you would want to do with jets, in my red tops I have right now, the main is 120 and pilot is 125. My needle and seats are 2.0 and my spring is 95 grams. I have not ran these yet either, just sitting on my bench. This is just what my dual 46's came with so I dont know exactly what you wound need. I live in colorado so more altitude will change it up for me. also your going to need to tap your cases for a second pop of fitting for dual carbs. You can find nice set of 44's for 100 to 130 bucks some times (good deal if they are clean!)... so I would wait for a good deal on some nice ones. You should be able to get 60 to 80 for yours depending on condition. you can always buy a second one and make it a slave carb but you just be better off get two that came from the factory together.
N2 H2O
Previously Tbone550
- Location
- Charlotte, NC
Yeah buy a set that cam stock together. The internals can be slightly different if they came off of different skis. You will have to tap your crankcase for a second pulse line. I like prok flame arrestors, but it doesn't make much of a difference. Just stay away from k&n because they get clogged up when they get wet.
- Location
- New Jersey
Yea, i currently have a k&n and don't like it. Im probably going for prok with covers. I'm going to look around for carbs. I might not buy them until the beginning of summer, along with the head when i have more money. For pistons im looking at these:
http://www.pwctoday.com/f149/fs-wiseco-prolite-750-small-pin-pistons-354759.html
or
http://www.atlanticjetsport.com/index.php?l=product_detail&p=2835
http://www.pwctoday.com/f149/fs-wiseco-prolite-750-small-pin-pistons-354759.html
or
http://www.atlanticjetsport.com/index.php?l=product_detail&p=2835
N2 H2O
Previously Tbone550
- Location
- Charlotte, NC
I would definitely get the wiseco pistons. They're 1mm over sized, so your bore would need to be 1mm over sized also.
- Location
- New Jersey
Yea, im leading toward them too, but the left one in the pic looks like there's a chip on it.