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BellicoseBanshee

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Posts posted by BellicoseBanshee

  1. What is the current squish clearance?

     

    The stock head gasket for the 85-86 ATC250R is a three layer metal gasket. The first and third layers measure 0.009" and the middle layer is 0.020". A stock head gasket for the '89 CR250R is a one layer metal gasket, and it measures 0.009" thick, and it is the same size on the cylinder as the ATC gasket. If the TRX has the same three layer metal gasket as the ATC (I am pretty sure it does), you may want to consider trying a CR head gasket. Very easy and cheap way to lose 0.029" of wasted space...

     

    Make sure the surfaces are flat and without blemishes. The gasket is pretty thin and will leak much easier than a stock three layer gasket. If you do choose to use a CR gasket, it is a good idea to have a back-up just in case it leaks...

     

    I have heard of people separating a stock three layer gasket and using one of the thin layers as a head gasket. I haven't really looked into that, but it may be a possibility...

     

    Another thing to look into is having the stock head machined. Check out Wildcard Racing. The 250R Cool Head I have uses a head gasket rather than o-rings, and works just fine, but is more expensive...

     

    TRX250R.net B)

  2. How is that override working for ya while duning? You ever backload it on accident or anything? How do you decelerate the bike to not backload it?

    I have hundreds of passes on it, and many hours of dune riding. I try not to back-load and downshift on the fly, but sometimes it happens. It seems to be holding up very well. I always use the clutch to coast down hills after a run, and I try to keep forward momentum when duning. I am sure at some point, I will have to replace forks, but for now, it has been very reliable. It is not that bad to split the cases from the bottom when the time comes if the top-end is still serviceable.

     

    I pulled my ATC250R (a completely separate addiction) out of mothballs for the last ride we did in May, and next season I plan to use it for duning instead my Banshee (do not want to dune with OOF pipes).

  3. I disagree. I run a 4mill and all I have is a billet offbrand basket.

    I agree with not needing a Hinson basket, for there are other, cheaper, options. A Magnum basket is a great deal and a good value at ~$150.00. I opted not to even mess around with cushion and back-plate problems and purchased a spring-tension basket. I have seen the carnage the cushions can cause when they grenade...

     

    As for tranny I do not run an override tranny will not run one. I dont have anything against them, but a 4mill doesnt need an override. I had my tranny cut and it runs perfect and ive never missed a shift.

    I suppose need is relevant to a person's point of view. The main reason I went to an override was to solve a shifting problem while racing hills in the dunes. Other than measuring every spacer and clip in the transmission assembly, I could not find any problems anywhere. Everything was adjusted correctly. All the parts were serviceable with low hours on them. It simply would not shift into 4th gear under load and an override solved that problem. There is no doubt an override increases the total performance of the bike.

     

    I have only used a stock transmission and a duneable override with my cub. If a cut transmission works, that is certainly another option for the OP. I still would not run a cub without an override. It certainly does not mean it is the only way to go, it is just the best use of the power a cub offers...

  4. What problems will I have if I dont run the override transmission.

    The only problem you may have is shifting under power...

     

    I had a problem shifting between 3rd and 4th gears. I would have to let off the power and let the engine wind down a lot before it would shift into 4th. On flat ground, it was a little more forgiving, but on the hill, it was terrible. There is nothing like having all that power and not hitting 4th on the hill. Very frustrating...

     

    Some people seem to not have any trouble shifting, but I can tell you from experience, there is nothing better than shifting at full throttle. I gained a bike length or two on the hill when I switched to an override. After riding one for 2 years now, hours and hours of dune riding (even with an override), hundreds of passes up and down the hill in the sand, I would not run a cub without a duneable override...

  5. I am looking for a bike that will run around 90hp on gas and hoping this setup can make it happen.

     

    All new parts

    -68mm Cub Cylinders

    -Wiseco 4mil long rod 115 crank

    -68mm Wiseco pistons

    -Coolhead 20cc Domes cut

    -Mikuni 34mm Carbs

    -CPI inframe drag pipes

    -Fast clutch

    Suggestions to add to the list:

    Pingel

    Lockout

    TZ/Max Load

    N1-5 Duneable Override

    Billet Basket (straight-cut gears for added reliability, but not necessarily needed)

    39PWK Keihins for gas

    Drag port

    Shearers (maybe the new pipes coming out soon)

     

    what do they do to the cubs for porting??lower or raise exhaust ports/tranfers??make intake bigger??

    Before porting:

    beforecr.jpg

     

    After HJR drag port:

    afterg.jpg

     

    Kevin told me what he did to it. You will have to talk to him about the details involved with his porting. I did notice a difference before and after...

     

    You will definitely want a duneable override,one of the best mods you can do on a bike like that.Without one you won't be happy.

    I agree, even if the stock trannsmission shifts, this is a must have if you are wanting to line it up...

  6. Your new needles are longer because they are machined to meter the fuel supply differently than stock needles (or the ones you have) meter the fuel supply. The length of a needle, the diameter of a needle, and the rate and length of the angle of a needle all effect the way fuel is metered. Arbitrarily cutting the length of a needle will have a drastic effect on fuel delivery...

  7. If you are using the stock PWK cap adjustment screws, they may not have enough threads to let the slides open up completely. I purchased Mikini cap adjustment screws from a local joint. The threads are the same as the Keihin adjusters, but the threaded portion is about 5mm longer (I used a Kehin cap at the store to do a test fit at the store). I do not have the part number anymore, but the picture below will show you exactly what you need.

     

    They are the same as ones FAST sells (gold is stock, silver is the one you want)...

     

    CARB%20PARTS.JPG

  8. There are a couple of advantages to using the spring-tension basket/gear assembly...

     

    There will never be a need to screw with cushions ever again (I know the mess those damn cushions make when one or more decides to grenade), and the springs are much more durable and will also absorb the power delivery more consistently.

     

    Just a basket, inner hub, pressure plate, I agree, no need to buy Hinson anything. A Magnum basket is just as good and 1/2-2/3 the price. I use a stock inner hub and a stock pressure plate with my basket/gear assembly.

     

    If a person is going to spend $375 on gears and $150+ on a basket, jumping to the basket/gear assembly at $600 is not that much more money (if they are still $600).

     

    Either set-up works fine, so It really comes down to what you want...

  9. Building a 10 mill cub, is a straight cut gear and basket really worth the 600 bux or not? Thanks for teh help

    You are talking about Hinson's spring-tension basket assembly, correct?

     

    I have one in my 421 cub. Was it really necessary, no... Was it worth the money, yes...

  10. If I recall, on the '84 250R I used to have, the cases are split in a horizantal fashion (opposite of a Banshee).

    That is correct, the case halves are left-side and right-side, not top-bottom like a banshee. :thumbsup: As far as I know, all the ATC/TRX case halves are left-right oriented (81-82, 83-84, 85-89).

     

    EDIT: Just wanted to clear up the horizontal-vertical terminology...

  11. my banshee seems to slip the clutch (faintly) when you come into the powerband good and hard and i was just thinking about getting a lockout clutch, because from what i understand they work on centrifical force=applying more pressure to the plates at higher RPM's, i was wondering if its ok to run lockouts on dune/trail bikes?

    "Centrifugal force" does not really exist. It is a false force in the sense that it does not act on the body in motion, it only acts on the source of centripetal force, and it is equal in magnitude and opposite in direction to the centripetal force.

     

    The weights are moving in a circular motion, and if one of the weights were instantaneously released from the arm, it would continue in a straight tangential line rather than go straight out along a radial line from the center point.

     

    I know, it is nothing really important, and it doesn't realy matter...

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