sezian

Oil is very subjective, you can / will hear all sorts of stories / theories, but unless you're running the bike at full throttle 90% of the time ie Superbike racer then semi-synthetic will always be the correct choice. Running fully synthetic is an expense that's not needed and as long as you drain the old oil and re-fill with fresh oil it really doesn't matter what brand oil you use. Obviously you want motorcycle oil but that's all that really matters. And yes your mate is right about clutches, you will have problems running fully synthetic, the clutch is more likely to keep slipping than wear out. Doing the service yourself is very satisfying and a good cost saving from dealers / stealers costs. P.S. If you run the bike for a few minutes before draining the oil it will heat up and thin out enabling pretty much every last drop to be drained.

Okay, good advice - It's not broken, however it did seem to lack a little power when I rode it home ??? I've got the engine on the bench with the head removed, the barrel off, piston off and rings removed. I've de-coked the head and now plan to de-coke the piston, it seems okay apart from the build-up of carbon. The rings look okay but I'm not sure what can go wrong with rings apart from breaking ? Any suggestions of what else to do whilst the top is off ??? I've toyed with the idea of polishing the ports, not making them any bigger just smoothing out the rough surfaces, although I'm not sure if this will make any difference ? I know when I was young and running around with mates on Fizzy’s & AP50's etc a good de-coke always made things feel faster (not sure if that was ever the case) and just to know you've actually been inside the engine and it still works was a great buzz. Now many years older and a little wiser I'm hoping to get some well gained experience from other 2 stroke fans on what does really make a difference and what’s worth doing. Many thanks in advance.

Is it worth £10,000 ??? If you want to pay this guy's wages and cost of parts I would rather have him build a bike specifically for me, not something he want's to build. I have a feeling he may regret the offer of £7,500 he's already turned down !!! There's enough supermoto's out there and for £10,000 you could buy at least two with money left over to customise yourself if you want to be different.

STOP, DON'T DO IT. I've had a few bikes in my time and have put many miles on various tyres, Bridgestone were always my favourite until I switched to the Michelin Pilot Road 2 tyres, these are 2ct tyres and will outperform and outlast most other tyres, wet or dry. Tyres are a very subjective subject and all the manufacturers produce brilliant tyres, 99% of the time tyres will be much more capable than the rider, ( are you riding in the supersport series ? ). If you've got a good deal on a particular brand then go for it, I could recommend Continental and they come cheaper than most. I expect you've already made your decision and just want people to say the tyres you've picked are great ? You probably like the look of the tread pattern as much as anything else !!! The main thing is to have them fitted properly with a new valve and get the wheel balanced. All new tyres will feel great when compared to the ones you've just taken off, but just before you buy check out the Michelin's, the reviews are good and they suit Yamaha's well.

If you have nuts to remove on the exhaust headers that just will not give with all the suggestions above the best way I've found to remove them is with a small Dremil bit. Carefully grind away the nut (making sure you don’t go into the stud tread) and when you've got nearly all the way through tap off with a center punch or small cold chisel.

Why not get the files out and port it !!!

You need 2 stroke oil in the oil bottle (under the seat / behind side panel), if the oil injection system is working don't put a pre-mix in the tank as well as you will double the ammount of oil the engine is getting. Trust this makes sense to you.

I'm in Herne Bay. Bike is almost finished, I hope to have it running & road legal for spring - In this country I guess that means at least the end of March !!! Will have to compare notes with you some time. Cheers.

I’m interested to know if anyone has experience of completely striping the DT engine and rebuilding it? What parts are needed and where they can be sourced? The engine (when I bought the bike) seemed to be running okay (rode home approx 15 miles with no problems) and I was told it had new main bearings and a re-bore only a couple of thousand miles ago. The bike has approx 24,000 miles on it and has been used on and off for the last 19 years. Should I leave it alone if it’s running okay or would there be some benefit in a full rebuild? From what I can gather there’s unlikely to be much (if any) performance increase but would there be some possible reliability benefit?

If you are in the UK eBay has a good selection from secondhand to new "BIG ONE" exhausts are available for the DT175. If it's a 1978 I presume it's a DT175MX model in which case most parts from the DT125MX will fit. Not sure about changing the carb or what benefits this would have, I'm guessing the original was sized correctly for the bike when designed so it's going to be pretty hard to match it with something else. I would suggest a good de-coke new plug and a carb clean should set you up.

I also presume globe translates to bulb but not sure how changing the indicator bulbs would make a difference to the headlight power? Or how this stopped the battery going flat? I'm not sure I need a new headlight to improve the lighting on my bike, I've thought about getting a halogen bulb for the bike which I believe can be sourced from this company http://www.norbsa02.freeuk.com/goffybulbs.htm (not sure how you put the clever link in). And you should be able to get a bulb to fit the standard DT175MX fitting. This would be a much cheaper option than having to purchase a complete new headlight. The option you've suggested is still after all only 6V and unless the glass is poor or the reflective part of you existing headlight is corroded I can't see what the improvement would be? I think the fact the H4 bulb upgrade is mentioned / recommended this is the real improvement !!!

Can you explain what 3W globes are? and what a flasher tube is? I'm guessing the translation in the UK is something different? I like the idea of more power to the headlight so would carry out this mod myself if I can work out what's needed. Any help apreciated.

I'm interested to know if you got the exhaust sorted from the "Big One" ? Also if you have, and got it on the bike what sort of difference did it make ? I presume it was louder? but was there any noticeable difference in performance ?

Does anyone know anything about setting up these engines without points ??? Any help and advice apreciated.

I think the ignition needs adjusting, there is a slight flat spot at 3500-4000 rpm which no amount of fiddling with the carb has fixed. With a strobe the timing is spot-on but it "jumps about" at the flat spot rpm, and I have been told the air gap in the pick-up may be wrong. Can anyone shed some light on this and explain how to cure the problem ???

I ordered a new seat cover from Wemoto for the 175 and was sent, what looks like the right size cover but clearly marked DT50MX. Have written back to them (as it's only just been delivered) asking for an explanation. I'm presuming they think it's the same fit. Can you tell me what the difference is / are the dimentions smaller or larger in some places ??? As I mentioned it looks right but as yet have not tried to fit it, I don't want to struggle only to damage it and then have to return for a replacement. Thanks for your help.

Does anyone know if a seat cover for a DT50MX will fit the DT175MX ??? I know a number of parts for the DT125MX are interchangable with the 175 but need advice on the DT50. Thanks.

I guess what you're planning is a lot bolder than what I have in mind, sounds like it will be a real screamer and will probably reach the dizzy side of 70 mph when you've thrown what sounds like over £500 at it. Are you able to help with any of the questions I've posted. Thanks.

I'm currently 3/4 of the way through the restoration of a 1981 DT175MX, with powder coated frame, swinging arm etc, new plastics and full s/s nut and bolt replacement. As yet I haven't touched the engine, it was running well when I bought the bike having ridden home approx 20 miles everything seemed fine, however top speed was just over 60 mph with the revs just under the red line. Front sprocket is one tooth up on standard, rear sprocket standard. The exhaust is standard ( in good condition ) with a standard end can, are standard cans restrictive ? I do have an expansion rear pipe that I was give as a spare, is this worth fitting ? I was also told the reeds are carbon as opposed to the standard steel, not checked yet, do these make any difference ? I'm hoping to increase top speed but not expecting miracles, have ordered a new front sprocket 2 teeth up from standard to slightly raise the gearing but need to know what other mods are cost effective that will give a performance increase. The engine was re-bored approx 2000 miles ago with new piston etc, I will remove carbon build up on head and piston crown but want to know if polishing the ports will help ??? Any information, advice or suggestions would be much appreciated. Thanks.