DT125R FORUM

Well this last month a disgusting amount of money was dropped on parts for this engine. [image: PXL_20260514_154633826.jpg] Two Keihin PWK 28mm Carbs Two Vforce Reed Blocks Billet Inlet manifold EBC Clutch Kit + Heavy Duty Springs 6 TZ750 Genuine Clutch Springs Zeeltronic Ignition System Billet Kick Starter Lever Magura Hydraulic Clutch Lever Chariot Performance Billet Clutch Basket Wiseco Blaster 200 Piston (573M06800) Modified Idle Gear with bearing [image: PXL_20260519_090422306~2.jpg] [image: PXL_20260519_090204554~2.jpg] These Wiseco pistons replace the stock Athena pistons due to the 115mm long rods I'm running and the +4mm stroked crank shaft. The head still needs to be machined to accommodate the longer stroke and the wrist pin on these pistons is different to accommodate the longer rod. [image: PXL_20260512_082334371~2.jpg] This idle gear is lovely, totally unnecessary but was only £60 but seemingly not available to purchase anywhere I looked. [image: IMG-20260507-WA0005.jpeg] The Magura wasn't cheap, but it's going to be necessary when running all 6 TZ750 clutch springs just to keep the power from slipping the clutch. [image: PXL_20260530_084354385.jpg] (the other two springs are in the post I had to source elsewhere). Now that I have the basket, I can finally assemble the clutch basket with my straight cut primary gears. [image: PXL_20260519_091147857~2.jpg] Basket is beautifully made, claimed to be the best on the market and I can see why. It was missing the Belleville washer that sits between the basket and the fastener plate, I bought a genuine basket to chop up and salvage but it wasn't on that basket (apparently they're fitted to 1986 models and later). I managed to find a company that sell them so ordered from them and fitted. Wasn't cheap but I'm glad it's in. [image: PXL_20260519_091204926~2.jpg] [image: PXL_20260527_182919884.jpg] I did replace the steel bolts with some lighter titanium ones (hopefully they withstand the abuse the basket is going to take!) [image: 20260522_143841-COLLAGE.jpg] About 50% of the weight, but hopefully not at the expense of strength! [image: PXL_20260527_183632013.jpg] The washer is installed with the raised edge facing you. The fastener plate will clamp down onto this edge. [image: PXL_20260527_183640084.jpg] [image: IMG-20260530-WA0000~2.jpeg] Engine is coming together nicely now though.

@calum said in Athena 170 porting: @lllDennis I read that the port timings were off by 3mm because apparently the barrel was based off a dtr200. How true that is... Would love to see before and after dyno pulls though. See how the stock Athena compares to a modified one. I have compared Athena 170 kit vs 3MB P (and 2RH) cylinders, the only 2 things that's off the athena kit is the piston taller than the stock,the ports are exact copy off the 3MB just a bit wider and the c port is little lower and matches more a 2RH cylinder The 170 is a mix between the 200cc casing (for the cooling canals and ypvs location) and 125 portmap internally.I searched for a piston that has the dimensions of the 56mm and with bore of 65mm but there is not,only some aftermarket forged that are max 61mm have the right piston height (pin to top).