On a standard derestricted bike you should change them at about 8000-9000 miles, I've done bout 8500 on mine so far and it's still going strong, I've heard of them lasting 20000 miles before but I think it's partly your luck really. If you've tuned the bike though, ie upjetted it, powervalve locked open, racing exhaust etc they need replacing a lot sooner, my friend Tim did all this to his nearly new DTX and got only 3000miles before it popped.
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I won't do it if you won't talk about your hands being too small
I personally wouldn't bother changing the rings themselves.I would use a new piston too.Measure the bore while your in there.If its worn then a rebore with new piston is the only way forward. You are essentially putting factory fresh rings into a run in and worn cylinder.Not really good for efficiency. Place your existing rings halfway in the bore and measure the gap between them.Check in the manual to see the service limit.You may find that they are fine. Mileage? Well depends on a whole lot of variables really but a hard ridden motor on good oil should last about 6000 road miles at least
How would you increase the compression? I think my bike would feel VERY dangerous with 47 HP, after fitting a rear knobbly on rough roads the back end bounces all over the place it's really not safe above 75 anymore....and it doesn't feel as keen to get there anymore either... ****ing Sam (my mechanic friend) the ****, i told him I wanted a Trailwing!!! But HOORAH!!!! I've passed my bike test today! No more L plates for me! Aaaaah....the bike looks so much better without L's and it's gonna be mint being able to take people on the back. Would it actually be possible to get 47 horses out of a DT?
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I won't do it if you won't talk about your hands being too small
125 GP bikes .... absolute peak of develoment, HUGE SUMS OF MONEY ... Late 50's HP ??
250 GP bikes ?? 105 HP ???
Big bore DT ... using Existing inlet / exhaust technology fitted to DTR's [not the Gucci KTM rotary valved etc ...] Tuned for top end HP - High Compression ... ?? Mebbe 30 Hoss at back wheel ??
Blower ?? Not practical ??
Nitrous Kit ... ! Suppose you could hit 47 hoss for a few seconds, but engine reliability would be in min's not thousands of miles !!
Raise compression by skimming head on a miller, thinner head gasket / thinner base gasket ... Though if you take too much off, piston tw*ts into head & fooks engine !
Congrat's on test pass
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Trailwing Good road tyre ... used to run em on DRZ's .. real forgiving at rear, they don't just let go, but give loads of warning first .. Love Em' !
What's your Knobblie ? Post Pic .... !
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Blue - DT 125 RE - '04 - First Of The Leccy Start Lanza'Like Bikes !
47 bhp can be attained in theory but there would not a lot of original parts of the dt engine left.Modified crankcases,clutch and possibly the gearbox at the most. GP 125 bikes make around 50-65bhp GP 250 makes around 110-130bhp
A tuned dt using stock or modified stock parts with a few trick bits would make around 35bhp at a guess.I'm talking mostly top end work here like porting,flowing,matching the head and transfer ports.
A nitrous kit can be used reliably on a 2 stroke but with a bit of common sense.Flicking the switch every time you see a bit of pussy at the side of the road will result in early piston demise.A mate of mine had gas fitted on to his trick lc125 with 175 big bore.The motor held up fine but quality engine internals are a must! His bike used to shock many RGV/TZR 250 kids!
The trailwing was an amazing tire! Even after most the tread had gone it still stuck to the road like anything, and it was reasonably good off road as well, so long as the mud wasn't too thick. The one I've got now is a Bridgestone 'Gritty ED668' if that helps, I'll try and find the battery charger and get my camera on the go to show you. it's fairly knobbly though. It's not actually that bad on corners or in the wet, it just makes the back end feel somewhat unstable. It's amazing offroad though, the back end feels too rigid almost I'm not used to the amount of grip. I really don't like the idea of nitrous on a 2 stroke, has anyone here ever tried it? What about things like increased compression, or big bore kits? How does the motor hold up?
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I won't do it if you won't talk about your hands being too small
Increasing compression can give more power but you can't just guess what will work.You have to start measuring squish bands to see if power can be found. Increasing comp will also make the engine run hotter so it wouldn't hurt to use a product like 'water wetter' that can lower the coolants temperature especially if running high rpm often. Big bore is the main way of getting a reliable power increase.The dt crank is as tough as old boots and as standard should take up to 35 bhp comfortably. My old rd lc bored out to 175 had raised compression by not using a head gasket.Instead the barrel was milled to take two o rings.This had an added benefit that the coolant could flow faster through the top end.My engine held up fine and i had no problems with it even running the stock crank. Nitrous is fun,fun,fun but you can only really use it at full throttle.If you shut the throttle off while gas is still flowing in it tends to 'diesel' I.E. it still ignites the mixture by compression alone so hitting the kill switch won't slow it down either.This problem is very rare but does happen.My mate did just over 4k on his 175 gassed motor before he sold it.The engine was fully rebuilt before the bike was used and we had to modify the clutch to stop it slipping.
Im with you, up to the '0' Rings, Vespa PX Motors have base gasket, but the [Air Cooled] head is sealed by O' Ring But how is coolant flow improved by O' Ring method ?? Is it because the gaskets aint' flapping in the flow where they overhang into the coolant path ??
Nitrous .. m8's 50 had clutch issues Hit switch, engine screamed, clutch slipped, net result of power increase against acceleration ... NIL !
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Blue - DT 125 RE - '04 - First Of The Leccy Start Lanza'Like Bikes !
Coolant flow is increased because the head gasket only has small holes to pass the coolant. Using an o ring allows the full water passageway to be used resulting in as much more efficient system Nitrous.Heres a pic of mates gassed up LC 125 when he had it featured in Streetfighters magazine oooohhhhhhh ten years ago
Suppose you could hit 47 hoss for a few seconds,
