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High Elevations
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Last year whilst riding in Spain and Portugal, the bike tended to bog and slow and stutter on inclines.

So before this years trip I gave the carb the once over.

All good across Europe, but just before Ankara the problem resurfaced, the problem seemed to be mainly in mid throttle positions.

After a few carb strips, having washed air filter, checked jets, dumped 4 gallon of suspect fuel (ethanol added), cleared partly blocked fuel filter above inlet valve and lowering fuel level to 9.5mm. to weaken overall mixture.

This last fuel level lowering seemed to help, but had lowered overall speed, which I could live with.

The problem thne came back, and I realised that I had gained height in Central Turkey without noticing. So a quick push of the knob on satnav - 1500mtr.

What to do, wants more air, took air box lid off - what a revelation, it now pulls well over 2500mtr. passes - the journey continues.

The downsides to all this, are greater induction noise, and when to replace air box cover, overheating with possible consequences of holed piston etc. etc. at lower levels.

So have decided to remove cover above 1000mtr. - and seems to work.

Two things I did not try were smaller main jet - say 5 -10%, or passing a strand of wire through origonal main jet.

The removal of air box lid is a quick and easy fix on the road, and no river crossings yet!

Any comments?

 

Alec



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THETFORD. UNITED KINGDOM.



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Hi Alec

your steed looks like a mile munching machine how many countries have you ridden through? , I think as long as you ran the lid off at high elevation only you would be fine, and as you say fingers crossed there are no river crossings ahead and the plastic side cover would defleact a little bit of water. , Ive got a shakedown run planned for next week so Ive got a few ideas, Ive raised the needle clip to 4 , Im running stock airbox, stock snorkel, with staintune exhaust header weld removed.
2500 m is as higher than the highest mountain in Oz being MT Kozuszko at 2228m , I wonder what the highest a TTR has been to.

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Hi Dazza

 

Yeah, I may play with the needle height at some time, am in Irkutsk at the moment, must be about 300 mtr. - no problem. Will see what Mongolia brings next week after I get my visa.

 

Best wishes - Alec.



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THETFORD. UNITED KINGDOM.



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Livotlout, I enjoyed Mongolia on a 150cc Chinese bike a few years ago. The road maps (paper and electronic) were quite inaccurate at that time, and I bet they still are. Many unmarked roads, side diversions, places with multiple names, places with same name as other places maybe 100km away. Even some main roads seem to be in a different place to what the map says. Different maps show different roads as "main" roads. However, the roads and tracks were not difficult, and often you could find a way across country, as no trees in most of the steppes, and NO FENCES (oh, what a lovely country!).

A Mongolian road atlas bought in Ulaanbaatar could be useful, especially if it has Cyrillic script place names so the locals, (who are incredibly curious and helpful in the countryside, at least) can read it and point out a direction. My two cents worth - but, you probably guessed it already, having gotten to Irkutsk.

At one point somewhere in Mongolia, we came across 3 locals on one 150cc bike, with a flat front tyre which they were fixing by stuffing the tyre with rawhide strips to replace the tube - we lent them a tyre lever to finish the job.

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TTpower wrote:

header weld removed.


Sounds interesting! Is that a weld in the header pipe or a machining defect on the cylinder head itself? 

Brian



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Brian, Im guessing TTpower means the restrictive collar found in the front pipe?

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I'm thinking that too.

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Pete Brown

Keighley, West Yorkshire

'94 Yamaha TTR 250 Raid (with Open Enduro headlight, grrr...)

'54 plate Suzuki GSF 650S (Bandit)

Previously Yamaha YBR125, Yamaha TY125, Yamaha TY250



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I guess you guys are right. I suppose I was hoping that there was a lump of weld somewhere that I didn't know about and could be ground off thus releasing a few free bhp wink

Brian



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RE: High Elevations
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TTRfan wrote:

"...I suppose I was hoping that there was a lump of weld somewhere that I didn't know about and could be ground off thus releasing a few free bhp wink"


 Says the one with a 325!



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rattlyolddt wrote:
TTRfan wrote:

"...I suppose I was hoping that there was a lump of weld somewhere that I didn't know about and could be ground off thus releasing a few free bhp wink"


 Says the one with a 325!


 Those extra 75cc weren't free though - far from it cry



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I know Brian, I love the notion of having a 325, and the cost is the only thing that is putting me off. I will most probably end up with a WR450 or a dare I say it a two stoke KTM. However I do love my TTR at the moment.



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