2013 ec250r

[Jakobi]

Head pulled after 4 engine hours. Will post a pic of the piston wash. Shows its running a little rich, but that was known. Still need to measure up the squish, but quick peek in the jug it seems the port timing is much better than previous models. Matches up very nicely with a single 0.5mm gasket. Next stop head work. I might crank a squish sample out on a stock silver inserted S3 head as well just for shits and giggles. Pictures to follow.

 

[Jakobi]

Port timing - The piston still sits some distance above the transfers at BDC, however the exhuast port lined up perfectly.

Squish - Measured 1.85 - 1.90mm (3 x samples taken)

I was considering taking the time to measure the trapped volume but think I'll pass on it. Dave will be able to calculate it all anyway.

 

[Simmo737]

I remember talking to the previous importer and he thought the had dropped the ports like kato did in 2012, looks like the did!

 

[Jakobi]

I remember talking to the previous importer and he thought the had dropped the ports like kato did in 2012, looks like the did!

Does appear that way. Be interesting to see how the ports look when its time to pull the jug too. There was a massive difference in quality between my OEM 300 cyl and the S3 250.

 

[Jakobi]

So last ride I noticed it breaking up in the mid to top a bit, and also noticed overflow from the carb vents when rocking the suspension up and down. Decided to take the time to set the floats up, and took some pics as well.

This is the slide height from front and rear. Bike idled really well.

I also noticed that the newer carbs have a 3rd jet. Installed in the block. Appears to be a leak jet. Didn't note the number on it, but 85 comes to mind.

 

[Jakobi]

When setting the float height, remember to roll the carb on its side and find the point where the floats just contact the needle jet once seated.

This isn't far enough

This is too far

And this is where my floats were from the crate

 

[Jakobi]

Bending the tang a little will soon solve the issue.

And after a few small adjustments this is where my floats are set to now. Total distance from the edge of the carb body to highest point of the float is 7.5mm

When fitting back into the bike don't forget to route the breathers up to the airbox. The two at the top of the carb are the ones!

Then on another note, just for shits and giggles, I put 8mm preload onto the 5.4 rate spring (previously was 10mm on a 5.2 rate), and then took a comparison photo of the 2012+ shock vs the 2011-

 

[Jakobi]

Heads done! Should be at the post office. Will upload some pics and record the info later! Brithdays coming, and so is a 50T rear sprocket.

 

[wence]

I spoke to Donny at Scottys about routing the carb hoses into the airbox and he said he runs them up along the frame towards the headstem. This way if the bike gets dropped in dry conditions the overflow out of the hoses will not splash onto the air filter .
Seemed like a good idea so this is what I have done. I also ran just one up there as there is not really a need for both of them . They get enough air to survive from the one tube.
Cheers Mark

 

[Jakobi]

True that mark. Mine are still looped over the carb and then down before coming back up to the airbox. Bike would have to be rolling to get the fuel spilling out in any great quantity. Would be easy enough to route them to the front too.

Picked the head up and spoke with Dave today. Ended up reducing the squish angle from 15.5 degrees to 12.5 to match the piston. Squish clearance 1.2mm. Final UCCR of 13.2:1 down from 14:1 stock.

 

[wence]

Nice work mate.
I must get mine done at some stage although I am quite happy with the power as is.
I am getting 100k's in the Vic high country....not sure how good or bad that is?
What does it cost to do what you have just done?
Cheers Mark

 

[Jakobi]

I seemed to get pretty decent economy out of mine on its first ride too. I didn't measure it but it wasn't stupidly thirsty! Thats for sure.

TSP is around $240 aud for squish setup and compression. Thats GST inclusive. Dave gave me a bit of a discount on top.

I'm interested to see how she runs now.

 

[wence]

sounds good mate and I am sure I will hear what it is like
Cheers Mark

 

[Jakobi]

With any luck I'll have it back together today, and in the bush running similar trails I did yesterday Won't be a great test of the engine though as its been raining for days and traction is at a minimum.

Here's some pics of Daves work

 

[Jakobi]

Put her back together today with the machined head, carb with float height set, and shock with 5.4 rate spring.

I took it for a quick ride and the jetting saga began/begins.
Still felt a bit fluffy in the mid range with 40 N3CW#3 175.
Went to 40 N3EW#2 175 - Noticable decline in grunt off the bottom, but running much cleaner.
Then tried 40 N3CJ#3 175. I'll keep this for tomorrows ride. Feels pretty good, but probably could go up one size on the pilot. Air screw was at 1.5 turns and had a slight burble no load, but felt like it could offer more just off idle when chuggin a gear high.

Strangely, I think I'd like to try 40 N3EH#2 175. I think the richer straight diameter might give a nice meaty bottom end, and the leaner clip position a smooth strong mid to top.

 

[wence]

I like that needle mate. Just makes everything predictable ....to an extent

 

[Jakobi]

Yeah my mind got the best of me Mark.. just got back from the shed. Have thrown the N3EH in position 2. I'll give it a run tomorrow. The N3CW/J wasn't bad either. just ever so slightly rich on the transition from straight to the first taper. Pretty nice meaty mid range. We'll see how she goes in the morn! Brap brap!

 

[Jakobi]

I know some have said their Q silencers don't spooge.. well mine does with Amsoil at 45:1

The N3EH#2 felt a bit lean on the needle. Just a bit flat and not as strong as a half a clip richer is, so I'm going back to the trusty 40 N3CW#3, but I'll keep the 175 main for now. Bike still ran quite well over the 80kms or so we rode this morning. Lot of following cattle tracks through tight country. Good times and was lucky to get out of 2nd gear. The bike will definitely be a bit better with a 50T rear sprocket. Anyone know if I'll need to add a few links to the chain to slide it in? Should be able to just adjust the tension and sneak it in I'm hoping.

Suspension. It was wet again. Forks felt quite compliant over the small stuff, but I think was blowing through the stroke on the bigger things a bit. It looked as if they had been using all their stroke (clean) but we didn't do anything close to fast or rough. The shock with the 5.4 felt super harsh in comparison to how it rode last time with the 5.2. Its strange because it still felt like it was plush initially, but as soon as I got into some chop at speed it kicked and deflected everywhere. Possibly it was blowing through too? To the suspension guru's, what rate springs would you be looking at. I'm 75kgs without gear. Probably at least 95kgs with spare tube, tools, everything else.

Those 2 piece rad shrouds suck bat. Managed to have them unclip once already. Might have snapped the tip off one of the lugs. Also not really happy with the fitment of the gromets now the rad guards are on. Any suggestions regarding improving the fit and finish?

 

[gasmonkey]

Hey Jake on the chain thing,depending on tyre dimentions the shock guard will be ripped off if it is too close.My fat s12 wasted my guard in during a rev roll back.Was an old chain so I just replaced with new longer one + guard.

 

[Jakobi]

Cheers John. I think I'll take the time to see if the 50T rear off my 2010 model will fit with some adjustment. If not I'll wait till the 48 is toasted and then throw a new chain on at the same time.