pauls320

Several places sell a 3.5 liter replacement tank in plastic

The best advice to you would be to take your new fixer upper to a reputable bike mechanic to either fully sort it out for you, or at least give you a report card of what your looking at to fix yourself...and then go from there.? Best of luck

Hi Gary, Its pretty normal for a healthy trials bike to need a good strong kickover to start. What size of bike have you migrated up from? Maybe the kick lever is indexed too far forward on the splines...this can make it awkward to effectively cycle the lever when attempting to start the machine.

https://birkettmotosport.com/application/files/4015/1387/5661/Ossa-Transmission.pdf

Those year oem caps are made by Acerbis...might try checking there??

Alex, regarding the crank. Generally what happens is a new corod kit is ordered and then the crank is pressed apart with an alignment jig in a hydraulic press and back together with new goodies...Not sure what state of wear/condition your barrel is in ,weather its useable or not. If it is useable you now have to measure it up to figure which size piston to fit.. At the point your at there, like I said, a good shop...and a credit card would be good advice,... second really look over your bike and see if the shock is leaking oil..forks , etc and other issues that you might want to consider before proceeding?? In some cases this is the point that one might really think about stepping up to something a little newer?? Just my two cents, Truly wish all works out well there....(Set of engine gaskets and new o-rings for cylinder head,might consider a newer style metalized base gasket ,as they tend to last longer) Oh, Dont forget to label the fuel can and bike?

There are no drainage points on that crank/ combustion side of the motor. Transmission is totally separate so oil and magnet debris is not relevant to his immediate problems . Two tanks of straight fuel without oil on an old tired 2003 motor....your bearings and cages are breaking up...$$

Judging from your first pic, the top of your piston looks like its been smashing bits of metal between it and the head...possibly bits of con rod or main bearing debris or even a lost wrist pin clip?? Pic also has your piston ring rotated around and overlapping the pin, which it should not...maybe its fallen out? You might want to look at taking it to a reputable shop. Hope you get rolling again soon

You may find a ball end hex key wrench is what you need, most tool manufacturers offer them.

Another item to toss into the soup pot... . http://www.tatsuyoshi.net/toyota/mc/20090302/ybr125.html

Now that is Very interesting

I would check with the hellteam or possibly birketts

Generally most modern trials bikes are pretty reliable . The 2010-'15 sherco's did not have the best fuel tank system for reliability and were/are prone to problems...art least you did not get one of the ones with the formula hydraulics Hope you get her sorted soon

The pump is just that and not a fuel ''switch''. Check your fuel tank vent hose to make sure its not blocked and allowing pressure to build when parked and put extra pressure on the carbs needle and seat (which should be in perfect clean condition), proper float level is very important too.

CSP (costa special parts) makes a beautiful but a bit pricey replacement. Splat sells them on the site. I would call or message them to see if the 2013 + complete basket gear assembly is the oem replacement that cross references up for your application....scorpa version used this too. Please post back afterwards and let us know what you find out.

Pretty sure the position of the motor mounting bolts and swing arm pivot points are the same but the head support bracket may need to be customized as 125 and 270 barrels may be different height. Other than that , as cope mentioned there my be other issues...coolant hose routing , etc, 2011 was new style h20 pump if remember correctly...post some pics etc of your build for us

When installing the header pipe, its best to try make sure the inlet is mated flush with the cylinder before snugging up the flange bolts evenly. Its not uncommon for someone to shove header on ,tighten up one bolt and then try catch up the second one, which does not help the situation. If your worried about it you can carefully bend the flange back with an adjustable wrench next time its off. Now go ride

That was a good read, quite the eye opener. Thanks for sharing that link

Pretty sure those OEM Yamaha's bikes and motors are made in in China and have been for some time. My new Yamaha generator is exactly the same as one of the chinese makes with different stickers too, also seen a Yamaha scooter and it stated right on the serial# sticker that it was made over there. Should still be decent if company specifies certain build criteria/materials and supports their products..

All the previous model years, they used Yamaha's, probably still the same for newest version.

If you are not sure what length bolt to put in there, just purchase one of the correct diameter and thread pitch but a little longer and install your chosen sealing washer and then remove your water pump cover and trim to correct length allowing for slight washer crush room so it does not contact your impeller...and be careful you do not over tighten it.

The throttle cable sleeve slides into adjuster on carb end and socket on twist grip end and will still ''snap back'' when throttle is opened and dropped..but slide will not fully close if cable is not fully inserted on either end. It can dislodge and reinsert easily if cable is pulled, etc etc. Seen it happen many times.(it may already be back in the proper position now) The flywheel key shearing would not cause your problem, it would be a result of your adventure...when the heavy flywheel is spinning wildly and motor is quickly stopped, sometimes the taper is not enough to hold the position and the key gets sheared off (inertia). This key holds your flywheel and ignition trigger point in the proper position to fire your spark at a precise moment, if your key shears, you will still have spark and your flywheel will still turn...just not trigger you spark at the correct time. best of luck

Ouch!, sounds like the throttle cable outer sleeve got pulled out of its base..if not a branchy ride area, I would look at a improperly routed cable..maybe poorly positioned zip tie job that made turning steering hard over pulled cable out?? Its a horrible sound when ya hear a runaway motor howling and then abrupt silence...they diesel and run even without ignition intact so its best to quickly smother exhaust outlet completely with gloves or whatever is handy (obviously only if rear wheel is not spinning wildly) Good luck and hope the carnage is minimal

Your gonna need to remove your skid plate and rubber engine cushion, before you can remove the case there

How about a Wulf ''Tri action'', looks like an Airoh trr copy, pretty sure they are a fiberglass shell.