DTR Build Up

ConnorDTR

Well here's how my first day riding my bike went,

http://i.imgur.com/WSsEKxc.jpg?1
Just a little pre mot prep, checking bearings are tight all lights are working etc

http://i.imgur.com/EPdAqV3.jpg?1
Admiring my creation

http://i.imgur.com/e9wIrrS.jpg?2
Passed with no advisories

http://i.imgur.com/UomhNDp.jpg?1
Went for a good ride with my friend Darryl, we checked out a few trails and i dropped my bike for the first time

http://i.imgur.com/2Rvbv2c.jpg?1
Went out later in the night to meet my friend from college and his mate as they fancy a DT too! However as soon as i got there the bike cut out, would kick over fine but wouldn't kick in. Tried bump starting it but still no avail, until the loudest bang every could be heard from my bike. This was when i suspected something was seriously wrong, as when you kicked it over there was a new, very questionable noise so i suspected my bottom end has gone.

http://i.imgur.com/NoMC7gZ.jpg?1
http://i.imgur.com/Zy06OBM.jpg?1
http://i.imgur.com/Qs0ch8l.jpg?1
When i got home (Thanks to my friend Dan for getting me in his van) I decided to get right down to it and strip the cylinder off in the freezing cold in my shed, Can see what i believe is called a four point seizure, to do with the piston heating up and expanding quicker than the cylinder so the piston gets stuck in the cylinder. When i drained the coolant i saw there was bugger all in there, 100ml at best and it wasn't the same colour as when it went in.... plus the coolant expansion tank has shot out its cap.

So i've ordered an athena top end gasket set and going to reuse the old cylinder with a quick rehone and the old piston as there are no marks at all, skim the head using Callums glass and wet and dry method, refill the coolant and hope that she runs again. Going to keep an eye for any white smoke and the expansion tank this time

Calum

@ConnorDTR that's the one mate. Flat surface as possible. Nice ciruclar motion.

Believe me, if you have read my.build thread then you know it can sort out a battered 21 year old engine that had clearly been run with the head gasket gone for a long time lol.

ConnorDTR

@Calum What grit did you use? Pretty sure i've got some fine emery cloth here aswell, or is that still too rough? I've got 2000 grit but it's those crap little rolls that are about 10 cm wide from halfrauds

Calum

Oh dear! Yes I see what's happened here. That barrel could get away without a hone to ne fair. But you're the right thing.

I was running my dt with too much fuel and it bore washed and scored similar. But wasn't the end of the world. Still runs.

Calum

@ConnorDTR pretty sure it was 120, 240 &460

ConnorDTR

@Calum That's the cylinder i'm going to save for a proper hone or if need be a rebore, also not going to use the same place as last time, £140, supplied me with cheap gasket set and a mitaka piston and it took 2 months... Think the reason it didn't run was because all the compression was leaking past the head gasket then. And that's pretty low, quiet a rough grit then? I have some 400 grit from doing my wheels, i'll give it a go tomorrow cheers

Calum

@ConnorDTR a rebore is 30. Forged piston is 60 and a genuine head gasket is 20. Done deal. I get mine done at Yamaha.

ConnorDTR

Gave my head the gentle skim, used 400grit wet and dry as that's all i had, just means it takes longer to skim down the high spots if anything.
http://i.imgur.com/9XG04L0.jpg?1
Used the cookers glass top, just because it was a bit more like a workbench lol

http://i.imgur.com/kRSEAhz.jpg?1
Here's the head in question, as you can see it's looking rather ugly. Did the old straight metal ruler over the head and see if any light passed underneath trick to see if there was any warpage, to my eyes i couldn't see much light. But i suppose a mm is like a mile when it comes to warpage. Haynes states anything more than 0.03mm is buggered.

http://i.imgur.com/t41qiAV.jpg?1
http://i.imgur.com/dVFpdzd.jpg?1
This was after the first pass, looks a lot better, none of those huge scratches and the surface is becoming a lot flatter.

http://i.imgur.com/9Oe9qRi.jpg?1
This was the state of the first sandpaper

http://i.imgur.com/lWPfBO6.jpg?1
This is what i ended up with, i still believe that maybe i should just go a grade higher to get a more smooth finish. But atleast the ring of dirt round where the cylinder meets the head has gone.

Calum

@ConnorDTR you will want to do both the block and head mate since they are both ally.

Nice idea I like that. Can't imagine my old dear would be pleased if she caught me doing that back in the day haha!

ConnorDTR

@Calum It's going onto a different cylinder, i've got 2 lol. This one originally came with the engine, i just didn't want to use it because the bottom bolt for the powervalve cover was fudged. But i checked out this cylinder with the ruler and i couldn't see any light coming from underneath the ruler

But yeah i did wait for my Dad to go to work before i started doing that, he'd have actually strung me up if he saw this

Calum

I always skimmed the barrel just to clean it up. Make sure it's legit. I always used the paper after I finished the head. Cleans it up nicely.

ConnorDTR

@Calum I'll have a look to see if i've got anymore paper, you are talking sense

ConnorDTR

Well it's been a good 16 days since i uploaded my last update where i was on my way to fixing the bike, since then a fair bit has happened.

The headgasket skim and new athena gaskets worked a lovely treat, i'm no longer burning coolant or having any bubbling in my expansion tank. So that has sorted out my overheating problem. However that was actually nothing to do with the reason why my bike broke down, there was plenty of compression even though there was scores on the piston and cylinder.
http://i.imgur.com/njWanLL.jpg?1
*The excitement of my gaskets turning up
*
http://i.imgur.com/uMgOotS.jpg?1
To be fair, working on this engine is absolutely piss easy

http://i.imgur.com/A64U8GY.jpg?1
First time using this baby, 22nm for the head nuts

So when I put the engine back together and expected it to kick into life i was quite disappointed, kicked as hard as i could but nothing happened, i also noted a new grinding sound coming from my bottom end. So disheartened i decided "Fuck it" and put the bike back in the shed for next months payday to be spent rebuilding this engine. But a few hours later i thought i'd take a more diagnostic approach to it, i'd see why the bike wouldn't start. Decided to have a look at the spark plug see what it had to say, it looked completely fine. So i'd see if i had any spark, earth the plug to the cylinder and kicked to see a spark, however there was nothing. That was a start to getting her back, automatically assumed that it would be the coilpack.

Waited to borrow a multimeter from a friend, but still wanted to know what this new grinding noise i was hearing. Tracked it to the left hand side of the engine lol, guess where this is going. Took the side cover off and found that the flywheel had worked it's way completely loose, how embarrasing. It was just spinning on the crankshaft. I never actually tightened it up properly. So i put the bike in gear, held the rear brake on and tightened the sucker as much as i could. Now that it was tight i kicked the bike again, bursted straight into life. What a relief, makes all the same noises as before, a strange ticking (like a ratchet) noise which i fear are my big ends or crank bearings trying to escape from where they live.

Anyhow i rode off to see my friends at the pub 8ish miles away, made it without any problems to be fair, apart from hitting reserve right outside of the pub. That scared me a bit, not used to a bike with a manual petcock.

Anyways the bike was working all fine so i decided to take it to college, 20 or so miles away. Got there perfectly and all. On break i decided to show my friends the bike and we'd go for a little ride/drive. 2 minutes in and my throttle cable gave up the ghost, however it had only came out of the weird slider thing in the junction box. So i borrowed some tools from the college and just put it back into it's holder thing, however the bike was now idling like a sack of shit. I had no clue what was happening, but it needed choke on to even get it to start and i had to play with the throttle to keep it going. I knew that this meant some sort of an airleak, but i couldn't fix it there at the college i was going to do it at home.

So it came time to go home and everything was going fine, apart from having to ride with the choke on and play with the throttle at the lights. About half way through my journey the throttle cable went again, i would NOT recommend the yambits throttle cables. They had this problem of coming loose in the junction box and also there is no oil pump adjustment. So i'm stuck at using 1l of oil every 200ish miles lol.

With no tools on me i pushed it to my friend who worked about 15 minutes away, got it all fixed and then continued my way home vowing to put the bike away until i had fixed all these problems. Well i got going again then my bloody flywheel worked loose again, bloody thing. Called up yet another friend to bring me some tools, tried to get the flywheel back on however it had at the woodruff key. With no access to a van and towing a bike being the scariest thing i have ever attempted. I decided to try my luck pushing the bike the rest of the way back home. 3 hours later and 5 miles up the road, me tired as anything, in the dark, cold and it was tipping it down, absolutely starving and thirsty i gave up. Finally got a van and got home. Never wanted to see the bike again.
http://i.imgur.com/68Ifl4U.jpg?1
Much preferred the car in the past few days, such a sense of security. Also alot warmer

However come today i've been rounding up a new woodruff key, a washer for the flywheel, some thread lock and soon a new throttle cable i've got to work. My stator is in one hell of a mess, the flywheel has destroyed most of the coils. But i fitted my new key, put the flywheel onto it, slid the washer onto the shaft, put some thread lock on the nut and the threads. held the flywheel with the correct tool this time and used a 1/2 ratchet and 17mm socket (brother has my torque wrench the only time i've actually needed it) i torqued that baby up good and proper. Couldn't move it anymore with a massive ratchet. The spec on this is 56 Nm if anyones interested.
http://i.imgur.com/tJBFFuH.jpg?1
here's the offender, nicely sat where it will hopefully stay for a while

So the bike starts again, scared to ride it anywhere now so going to sort out some breakdown cover, still need a new throttle cable and want to give it a bottom end rebuild as it sounds like a bag of nails

Sorry for the short novel

ConnorDTR

God damn just realised how much i look like i'm sponsored by halfords with all the tools lying around lol, making the most of my trade card

Calum

Oh dear not good.

That's kinda why I prefer the DTRE flywheel. It locks the woodruff key off from ever moving.

I have had the throttle cable go. Had to adjust idle so at least I could sit on it at 3mph home lmao.

I like driving a car, but it don't beat the bike.for me. Even the Starlet. Love it but give me a dt.

ConnorDTR

@Calum
I've not really seen the DTRE flywheel, but to be honest this could have been avoided if i torqued it up properly in the first place. Just makes me not trust the bike much as i've broke down twice now in one week.

I will have to buy a proper yamaha throttle cable, but i tried to do the whole coast thing but my reed cage had come loose so the bike wouldn't idle at all.

But at the moment i much prefer driving a car, even if it's not a special car. But i suppose that will change when i trust the bike and it's warmer weather

Calum

@ConnorDTR yeah been there lmao. I feel your pain. I will no doubt go through the same problems as you whilst I get my bike up to scratch lol

ConnorDTR

@Calum Nah just tighten everything up properly and you'll be sound pal lol

Calum

@ConnorDTR There will be something I'll miss that's for sure!

ConnorDTR

Right well it's been 2 months since the last update, and 300 miles later the bikes shagged again. Only conked out on me a mile from home this time though luckily, on a lovely hot day too. The first we've had in ages so home now and i took the spark plug out, all looks fine there. Did the stupid thumb over the spark plug hole and kicked the bike, it couldn't even push my thumb off. So i put some oil down the bore and kicked again. This time it actually had compression.

So obviously need to do a top end and properly this time, but i've also got a horrible clunking sound from the bottom end and without knowing the previous history of this engine i'm going to do a full rebuild. However obviously this takes time and money, something which i'm short on at the moment having just renewed my car insurance, having to pay for uni deposits etc. So this is going on the side again for a while Right at the beginning of nice summer too! been getting tempted at selling it to be honest, but i've put so much work into this! I don't really enjoy it all to much, scared of it constantly breaking and hardly enjoying offroading. The bike has no low end power and is hard to cruise at a single speed.

So thinking of either selling up, breaking the bike or stop being a little bitch and rebuild the engine, fit a 3 wire servo and go supermoto! Sad really i wanted a bike for summer

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