I've run into a bit of a snag on my TM. I can't find the information I need to choose the correct rear spring to match the .48 front fork springs that I'm about to put in the KYB forks. The fork springs are identical to 4 stroke Yamaha KYB springs and luckily I already had a set from previous bikes. The problem is TM has a different shock linkage ratio then most other manufacturers. The spring that came on the shock was a 4.8 and it seems to be about right if I weighed around 180 lbs so to get by during the break in period I put a bunch of preload. Now it's time to service the fork and shock and get the break in oil out but I don't know what spring to buy and I'd rather not use trial and error and end up buying 2 or 3 springs to get the sag right. I'm guessing about 2 steps stiffer to a 5.2 would be close but at $160 per guess I don't want to be wrong. If anyone has the knowledge to calculate it I weigh 210-215 lbs and I'm 6'6" tall so because of my height I usually go on the stiff side on the rear if it falls on the line between 2 spring rates.
Buy your springs from Summit. They sell coil over springs for automotive applications that fit and start at about $50.
I checked automotive suppliers and it would be a big savings if the correct spring is available but unfortunately I couldn't find a match for my shock spring. I checked multiple different sources including the spring manufacturer/distributor. I now have a spring on the way from JM Racing suspension in Illinois, a 5.2 should balance out the .48 springs I'm putting in the forks.
Always been intrigued by TM, especially the EN300FI four stroke. If California wasn't so tough to register bikes, I'd probably pull the trigger, but I always want that plated bike. Motoxotica in Vacaville, CA sells TM, Husky, and Beta so there is no issue with parts and access to an awesome dealer. As long as I live in Northern, CA, they are the reason why I will always have a Husky or Beta. Looking forward to hearing more about the TM as you go.
I got the springs installed and as it turns out the rear spring dementions match up with Showa/KYB shocks from around the 1999 2000 year model Japanese bikes. Since the linkage ratio makes it possible to use a 5.2 spring for a 215 lb rider it would be possible to get the correct spring even if you were a really limiting factor might be how stiff of a front spring you could get to balance the rear and get the correct sag. Fortunately since it used the 4 stroke front fork springs which are longer springs than the 2 stroke Yamaha, the springs are available in heavier weights and also last longer before fading because they are not being worked as hard as a shorter spring in the same application.
Now that it's sprung exactly how it should be for me it is even better handling and the only issue I was having which was keeping the front wheel on the ground has be resolved. I had a conversation with the importer and my dealer and the FI 2 strokes don't give performance gains but do meet the euro regulations so they are offering the FI 2 strokes in the USA but because of the extra expense they are standard with a carburetor. Since you're interested in the 4 strokes I recommend you test ride one if you can. My son and a local Pro rider both rode a 2018 450 and said the engine was really good and kept pulling hard in the upper rpm range and unlike most 4 strokes it did not flatten out on top. As for the chassis I've found them to be open and comfortable for taller riders and the suspension works really good in stock form. I've had either KYB, Ohlins and Zokes forks on my last 5 bikes all of which were sprung and re-valved and I prefer the KYB spring fork. (the TM is still stock and good enough I doubt i'll get a re-valve). The shock body is made by TM and I suspect the internals are either KYB components or Sachs which are basically a copy of KYB.
What a sweet alternative to the husky..no pumpkin posers riding tm.. I'm seriously thi king on pulling the trigger..
I agree, I would definitely want to demo out a 300FI before going all in. I used to have a 15 Beta RS500 and despite it being an exceptional bike for a lot of different areas, I never seemed to gel with it that much. I got it late in the year so the price was pretty decent for a brand new bike, but it was still a big purchase no matter how you look at it. I was able to attend the Beta Demo day out here in Northern CA and came away with a lot of good perspectives that could only be realized by physically riding the different bikes. Lesson learned... I had researched, read, and watched everything I could find on the 350 and 390 and before the demo day was convinced the 390 would be my next bike. After the demo day the 350 was the clear cut winner, no comparison for me. With all that being said, I am back on a used Husky TE510 again haha. Once my truck is paid off, then maybe I'll revisit the idea of a brand new bike, but for now I just research and dream.
