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About twr7cx

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  1. twr7cx

    88 KX125F - disappearing gearbox oil

    Thanks William. Appreciate it.
  2. twr7cx

    88 KX125F - disappearing gearbox oil

    Thanks for the reply. I'm not sure why your so offended by the fact that the first paragraph of background information is a copy and paste from a older previous post on a different topic on the same bike but sorry to have caused you such offence. Finances are a consideration with this bike - there's a point where the potential costs for repair would make it worth scraping the bike and purchasing a newer replacement in better condition rather than repairing. I won't both elaborating on that further - that's a personal decision for me to make at the relevant time. I have a small amount of experience in working on motorbikes and little to none on two-stroke bikes, as all my others are or have been four strokes. My main experience is in automotive. So I was hoping for some information to help guide me on what would be required/recommended to resolve this given some of the unique intricacies of two strokes. I understand that the gearbox has oil in it which, unlike on a four stroke, doesn't flow through to the engines crankcase too. The power must be transfer from the crank into the gearbox to be able to eventually turn the rear wheels and, given the first point, there must be some sort of seal there to stop the flow of oil into the crankcase where it doesn't belong. Given that the oil level is going down without any falling on the ground its likely that mlatours suggestion of it leaking into the crankcase is valid and therefore the seal is at fault. What I was hoping to get an understanding of from this thread is the requirements for accessing and changing that seal - i.e. does the engine and gearbox neatly seperate without disturbing anything else and its then just a matter of removing the old seal and fitting the new, or is it a bigger job such as is the seal accessed through the crankcase or does the gearbox have to be opened up to access it? These would effect what other parts, gaskets and seals would be required in order to do the job. EDIT: I found the attached picture of the bottom end which looks like the gearbox housing and crankcase are a single piece in two halves. Anyone able to advise which are the likely seals that may have failed to allow the gearbox oil to enter into the crankcase? EDIT #2: just reread your post and realised that you said the seal can be replaced from the outside. Can you advise which/where on the outside?
  3. I've got an old 1988 KX125F here that we purchased years ago for next to nothing. It's in good condition for it's age and is used by visitors to have a bit of a ride in our paddocks and has taught many people to ride for the first time on it. The exhaust is particularly oily and the gearbox level goes down without leaving a puddle on the ground. I assume therefore it's leaking internally. Can anyone advise on what's required to rectify (aside from a new right hand side crank seal)? I'm particularly interested in what else has to be disturbed/dealt with to carry this out. My concern is that the bike has a very low financial value, it's only used by others and limited - 10 hours a year at most - so I'm hesitant in how much time and money to spend on it.
  4. twr7cx

    88 KX125F

    Thanks for the all the replies. The air filter gets cleaned and reoiled fairly regularly. Probably within every 3 to 5 hours of riding. Spark plug is changed reasonably regularly and I run a fuel filter between the tank and carby which is changed every now and then. Aside from changing wheel bearings, tyres and tubes a year or so ago, no other maintenance has been done on it in years. Gearbox level has been going down for years without leaking on the ground so imagine the this seal is gone. Maybe it's gotten worse now though and effect the running too. Might have to finally do something about it then. I've just recently pulled the carby apart, cleaned it out thoroughly, adjusted the float height and and reassembled. Bike went from refusing to start even when rolled down hill to starting again quickly after a light easy kick. I think it's definitely time for me to inspect the reeds then.
  5. twr7cx

    88 KX125F

    I've got an old 1988 KX125F here that we purchased for next to nothing. It's frequently used by visitors to have a bit of a ride in the paddock and taught a fair few people to ride for the first time on it. Having an issue where it seems to be under powered and not wanting to 'hit power band'. I believe that it is running rich and this is the cause: It is smoking heavily and there is a lot of unburnt oil around the exhaust. I use 32:1 ratio petrol to oil. When riding it feels like it is lacking power. Twisting the throttle further sometimes even seems to slow it down a bit rather than get it going more. Fuel economy is bad. I ran out the other day in the paddock but noticed that in the two minutes before it died on me that the bike suddenly ran properly again - significant increase in throttle response, power and bike willingness and want to rev. This is my main reason for suspecting the rich running. I've tried adjusting the Air Adjustment Screw (ref 14 at ) and that didn't seem to help at all. I believe that this only effects the starting, idling and take off though. Some perhaps relevant recent history is that in September 2017 I tried to get the bike up and running again after eight or so months of not being standard. The carby was dirty inside and I had to pull it apart and clean it and I sought some advise on here about adjusting the float correctly So, any further advise/guidance please for how to tune up the carby?
  6. Wow, thanks for all the replies. I wasn't aware that the mufflers required repacking, and definitely not so regularly. Is that specific to aftermarket cans or do OEM factory mufflers also require that level of maintenance?
  7. On my 2000 XR250R I have a FMF PowerCore 4 that I personally imported to Australia from the USA. I've had the bike for years and perhaps my older age is now catching up to me but I'm finding it a bit loud. On the FMF website < http://www.fmfracing.com/Product/ProductDetail?CategoryID=42&BikeType=MX%2FOFFROAD&BikeMake=HONDA&BikeModel=XR250R&BikeYear=2004&ItemID=041020&imaConfig=Single&ParentCategoryID=31&Priority=13 > it says: "-Optional 96dB quiet insert available" Anyone know where I can purchase one of these (preferably online) that is compatible with my muffler? I don't have an FMF dealer locally to assist me...
  8. So I pulled the carb out again last night. Removed the float and needle valve. I then cleaned the seat using a cotton wool bud and toothpaste as per http://www.blasterforum.com/threads/easy-and-almost-free-way-to-stop-leaky-carbs.33335/ I then readjusted the float height. It just seemed strange to me and when I had the carb inverted and then at a 45* able it was the same. It just wasn't right. So I removed the needle valve again and went and found the old one - different heights! New one was 3mm shorter, hence the issue setting the float! Cleaned up the old one with toothpaste and a cotton bud and moved the retaining clip over (I lost the old ones clip which is why I replaced it), fitted it, adjusted the float height, reassembled and she ran on the first kick!
  9. I've got a 1988 Kawasaki KX125F which wouldn't start. I opened up the carby to find the inside coated in a crusty layer and the needle stuck. I have removed the old needle and replaced it. Before reassembling I adjusted the float height to 16mm in accordance with http://www.carbparts.com/keihin/needles_tuning/jetting_your_carb.htm and http://www.vitalmx.com/forums/Race-Shop,42/Float-height-adjustment-for-Keihin-PWK,1284568 . The float was a bent a bit crooked before so it took a bit of fine tuning - check out pictures at Reassembled and refitted to the bike. Turned the fuel on and it kicked over and started first time but when I looked down there was fuel flowing out of the top and bottom hose barbs on the carby: Any ideas on how to resolve? I assume that either the float height is incorrectly set and therefore not pushing up the needle valve to block off the fuel into the carb bowl or the new needle is not sealing on the old seat? The seat is a brass piece that looks to be press fitted into the carb and I have not seen replacements advertised (not sure how it would be removed either though). Is there a way to clean the seat (I've already tried carby cleaner spray and blowing compressed air)? Can I test which is at fault by removing the carb bowl, connecting the fuel and holding the float needle valve up to see if it seals off and stops the fuel flow?
  10. twr7cx

    88 KX125F Carb Float Valve Clip

    Awesome, thanks for the above. Apparently the part is interchangeable with OEM parts from a few different brands that must all use the Keihin PJ carb. The part numbers are: Suzuki Valve #13370-29F00 Kawasaki Valve #16030-1057 Yamaha Valve #4MX-14392-00-00 KTM #5463110000 Triumph #T1241033 I'm surprised that there isn't a Keihin part number too... Any advise re the float? Noting that as shown in the above pictures it's a bit bent up and uneven, is there a setting for it that I should adjust it to? EDIT: found this < http://scootrs.com/tech.cfm?tip=float > and < which might help.>
  11. twr7cx

    88 KX125F Carb Float Valve Clip

    Pictures of the dismantled carb: Of note is that the float seems to be bent up a bit...
  12. I have a 88 KX125F here that wouldn't start after being left sitting idle for eight months or so. Suspecting a fuel issue I opened up the carb to give it a clean and in the process lost the float valve clip (it sprung off while I was attempting to remove the float valve and is likely now lost in the grass), identified as 22 in the diagram below. The carb is a Keihin PJ. Any ideas on what the part number is for a replacement? Are they all the same or do I need to know what size (e.g. 34mm, 36mm, etc) the carb is? http://www.psep.biz/store/keihin_pj_series_parts.htm lists 'ADKH018104' as the part number but Google search doesn't recognise it on any other websites. A picture of the carb are in this old thread: https://thumpertalk.com/applications/core/interface/imageproxy/imageproxy.php?img=http://i1185.photobucket.com/albums/z343/twr7cx/IMG_4181_zpsd72c1795.jpg&key=872f56b0c72063a176584e8f83f2eee43b97a04aa7290f4febc298a2e263e9e4 Also, any tips for removing the float valve (needle valve)? It seems to be a bit stuck in there.
  13. Anyone able to provide any insights in regards to comparing the conventional front works (as found on a circa 2000) and the upside down (as found on a circa 2004) Honda XR250R? If one has access to both to select a pair for rebuild, which would be the pick? According to RaceTech < http://racetech.com/ > the standard suspension specifications for the conventional front forks are: I'm not sure on details for the USD?
  14. So had my first ride with the new suspension on the weekend - wow what a difference! The front is no longer bottoming out which is a great start, but it is so so so smooth, just takes the knocks. A mate of mine who until recently rode an XR400 of similar year and now just bought a Yamaha YZF450 which is only a few years old was super impressed with how it performed to when he took it for a test ride.
  15. twr7cx

    KYB Shock Rebuild Kits?

    Used RaceTech for mine, most of the seals are genuine KYB band.