forteh Posted May 24, 2015 Report Share Posted May 24, 2015 (edited) What's the throttle positioning when it's bogging down? Backfiring ( especially back through the carb) is indicative of a lean mixture. Sounds as though you could do with either a larger main jet or you might get away with lifting the needle a clip or two, that will affect mid throttle response though. Typically if it's bogging it's lean, if it's dull engine note and heavy smoke it's rich. When you took the plug out what was the last engine running condition? It will only give an indication of the fuelling on the circuit that was being used when the ignition was killed. Have a search through this thread, I'm sure I've posted up the correct method for doing plug chops in the past. What carb is it? Google for the mikuni vm tuning guide, it's got a good bit of info on how carbs work with the different fuelling circuits. The same information can be translated to most conventional carbs. Edited May 24, 2015 by forteh 1 Quote Link to comment Share on other sites More sharing options...
Tony Harrison Posted May 25, 2015 Report Share Posted May 25, 2015 Thanks, that's really useful info. I'm fairly new to carb stuff - in the past I've ridden plenty of two-stroke trials bikes (older Spanish ones) but never had issues like this. Running lean could well be it - this might explain why it happens when I open the throttle up. I think tonight I'm going to get the engine builder to ride it again. He did try it before but didn't find a problem, but at that point I hadn't worked out the conditions in which it misbehaves. Quote Link to comment Share on other sites More sharing options...
CC12345678910 Posted May 25, 2015 Report Share Posted May 25, 2015 (edited) Two stroke racers bible: a big loaded pull until it revs out then plug chop it. Cos i'd have said it was rich on the air screw myself, but thats a very simplistic way of getting it to work, not dialling in a set-up ie. the jetting n needle height being proper sorted. EDIT: You could have an air leak. If it's sucking post carb but pre cyl. that'll royally f**k you over and you'd be chasing your tail changing stuff for weeks. My ol fella preaches about this stuff called blue hylomar, and he's right, it's the absolute bollocks. I actually laughed in someones face when they tried to sell me some cranville instant gasket, saying "it's the same stuff". Nothing but nothing puts up with silko/105 octane acetone based ELF racegas mix for extended periods without reacting, losing it's stick and letting air in. Hylomar does. Trust me, I've scraped it off before as a punishment. NOT fun. Have a read Hylomar – Non-Setting Compounds Edited May 25, 2015 by CC12345678910 Quote Link to comment Share on other sites More sharing options...
forteh Posted May 25, 2015 Report Share Posted May 25, 2015 (edited) The air/fuel screw only really affects throttle openings from zero to quarter open, after that it's needle and main jet. Air leak post carb is a good call, I would expect it to affect the idle as well though. Blue hylomar is good stuff, although I've had more success with rtv silicone when removing the base gasket from the ccm (to boost compression ratio). There is also a loctite 574 that works much better but is about 30 quid a bottle. Edited May 25, 2015 by forteh Quote Link to comment Share on other sites More sharing options...
monkeyseemonkeydo Posted June 4, 2015 Report Share Posted June 4, 2015 Michael Dunlop has left the Milwaukee Yamaha team a couple of days into the TT fortnight because he doesn't feel the R1s are competitive enough to challenge for wins. Unprofessional much? Quote Link to comment Share on other sites More sharing options...
Luke Rainbird Posted June 4, 2015 Report Share Posted June 4, 2015 Few of the lads I'm on course with at the mo are desperately trying to get me to learn to ride. Tempting, but can't really afford to do it properly at the mo so will leave it for now. The seed has been firmly planted though... Quote Link to comment Share on other sites More sharing options...
Mark W Posted June 4, 2015 Report Share Posted June 4, 2015 Michael Dunlop has left the Milwaukee Yamaha team a couple of days into the TT fortnight because he doesn't feel the R1s are competitive enough to challenge for wins. Unprofessional much? Don't say that to Bongo I would agree though. As I also said on FB, seeing his reaction to his brother beating him at the NW200 last year and now seeing this doesn't add up to him having a particularly good attitude. It's fair enough if he feels the bike is dangerous or whatever, but he must have known or had an inclination earlier on that he didn't want to ride it, so surely he could have done it sooner so they could have got a different rider to potentially come in and see if it worked for them? Quote Link to comment Share on other sites More sharing options...
bing Posted June 4, 2015 Report Share Posted June 4, 2015 He'll get a private S1000RR and wipe the floor with all of them. To be fair, he's in a pretty good place to judge wether a bike is good enough or not. In other news, father has finally got old. Bought a BMW R1150r rockster and is selling the Ducati 999 Quote Link to comment Share on other sites More sharing options...
Mark W Posted June 4, 2015 Report Share Posted June 4, 2015 Surely you can judge that before the event, unless you haven't done enough prep? He's already got the BMW lined up. Quote Link to comment Share on other sites More sharing options...
monkeyseemonkeydo Posted June 5, 2015 Report Share Posted June 5, 2015 I've always thought he was a bit of a dick. Fast, sure, but a dick nonetheless. Edit: MD that is, not bing's dad... Quote Link to comment Share on other sites More sharing options...
bing Posted June 5, 2015 Report Share Posted June 5, 2015 Surely you can judge that before the event, unless you haven't done enough prep? He's already got the BMW lined up. Don't think he's done that much testing on the R1, plus it's a new for this year bike and I suspect not upto scratch, hence dumping them and maybe going back to BMW. He always looks on the ragged edge though, like there's nothing left in reserve Quote Link to comment Share on other sites More sharing options...
monkeyseemonkeydo Posted June 5, 2015 Report Share Posted June 5, 2015 Just watching the TT coverage on ITV4 and MD looks like he's about to headbutt anyone he's talking to... even when he's happy. Quote Link to comment Share on other sites More sharing options...
Mark W Posted June 5, 2015 Report Share Posted June 5, 2015 Don't think he's done that much testing on the R1, plus it's a new for this year bike and I suspect not upto scratch, hence dumping them and maybe going back to BMW. He always looks on the ragged edge though, like there's nothing left in reserve He rode it at the NW200 and at a test session in Spain from what I can gather. Like I say, it just seems odd that you'd leave it until part way through the fortnight to decide to sack it off... Quote Link to comment Share on other sites More sharing options...
ManxTrialSpaz Posted June 6, 2015 Report Share Posted June 6, 2015 Just watching the TT coverage on ITV4 and MD looks like he's about to headbutt anyone he's talking to... even when he's happy. I saw him in the paddock at the UGP and he seemed pretty grumpy/withdrawn from everything. Well, I say I saw him in the paddock, he didn't leave his truck unless he really had to. Quote Link to comment Share on other sites More sharing options...
CC12345678910 Posted June 8, 2015 Report Share Posted June 8, 2015 (edited) Don't think he's done that much testing on the R1, plus it's a new for this year bike and I suspect not upto scratch, hence dumping them and maybe going back to BMW. (Has since had Kiyonari's buildbase BMW shipped over. Has also had a minor spill at The Nook on it in the superbike race and is now reported to be hobbling abit. ) Milwaukee yamaha do roadracing when they feel like it, like it's a nice little hobby to do when there is a gap in the calendar and any effort will always be second fiddle to the BSB for them. IMO they are the unprofessional dicks (Fing cowboys is nearer the mark), not MD He's also stated that milwaukeeyamaha and the bike have not delivered. (BTW there is a president there - having previously left Connor Cummins looking like a total mug at the southern 100 a couple of yrs back, because his promised bike was 'suddenly called upon' for the BSB.) Michael also went on record apologising to the boys with the spanners, who had done what they could. However the bosses parachuting in the engine builder at the start of practice week (also straight from MD's mouth on manx radio) to pick up the slack instead of at the start of the development program like was promised, and a fastest practice time of 123ish was, i would surmise, one of the multitude of straws that broke the camels back. EDIT: For context, remember that 125 and a bit MD did on that XR69 at the MGP in 2013? A 25+ yr old bike powered by a carb'd road spec GSXR1100 engine, and I personally watched it spit him across the road & try to spear him into the tree on the exit of hillberry. THAT was faster than the new milwaukee yam. Edited June 8, 2015 by CC12345678910 Quote Link to comment Share on other sites More sharing options...
bing Posted June 8, 2015 Report Share Posted June 8, 2015 (edited) Did you see md's crash yesterday? Couldn't work out who hit who, but it looked like the back marker got in his way and Dunlop ended up skittling him off and tumbling off himself. Too much going on for him this year. Hutchison. What a guy. Brought a tear to my eye. Never has there been a more deserving winner Edited June 8, 2015 by bing 1 Quote Link to comment Share on other sites More sharing options...
monkeyseemonkeydo Posted June 9, 2015 Report Share Posted June 9, 2015 He wasn't sure what the backmarker did but he was either spooked by Bruce or tried to follow him through before clipping the bank right in front of MD and Dunlop had nowhere to go. Haven't heard what happened to the backmarker but take it he's relatively ok. Quote Link to comment Share on other sites More sharing options...
bing Posted June 9, 2015 Report Share Posted June 9, 2015 And so it rumbles on. Hutchy wins again. Guy martin cocks up again. Dunlop is hurting. Strange week at the TT this one. Not much mention of John mcguiness either Quote Link to comment Share on other sites More sharing options...
CC12345678910 Posted June 10, 2015 Report Share Posted June 10, 2015 (edited) Did you see md's crash yesterday? Couldn't work out who hit who, but it looked like the back marker got in his way and Dunlop ended up skittling him off and tumbling off himself. He wasn't sure what the backmarker did but he was either spooked by Bruce or tried to follow him through before clipping the bank right in front of MD and Dunlop had nowhere to go. Haven't heard what happened to the backmarker but take it he's relatively ok. 'Backmarker' was Scott Wilson, all ok bar a broken collarbone. He ended up mounting the banking like he was carving a wallride, then though sheer timing bashed fairings/barends with MD on the way back down. In other news, the noise of that Kwacker H2R on James Hillier's exhibition lap He mapped himself on strava; 206.9MPH down sulby and something like a 18.39 lap! Then the tech from kawasaki leaned in on the interview and said that due to the way it was geared that was absolutely maxxed. Found a vid that king of does it justice Edited June 10, 2015 by CC12345678910 Quote Link to comment Share on other sites More sharing options...
CC12345678910 Posted June 10, 2015 Report Share Posted June 10, 2015 'Backmarker' was Scott Wilson, all ok bar a broken collarbone. He ended up mounting the banking like he was carving a wallride, then though sheer timing bashed fairings/barends with MD on the way back down. In other news, the noise of that Kwacker H2R on James Hillier's exhibition lap He mapped himself on strava; 206.9MPH down sulby and something like a 18.39 lap! Then the tech from kawasaki leaned in on the interview and said that due to the way it was geared that was absolutely maxxed. Found a vid that kind of does it justice Quote Link to comment Share on other sites More sharing options...
bing Posted June 11, 2015 Report Share Posted June 11, 2015 Fackinell. He weren't hanging about to say it's not a race bike as such Quote Link to comment Share on other sites More sharing options...
trials owns Posted June 12, 2015 Report Share Posted June 12, 2015 getting the bike in for its mot tomorrow, im going to insure it tonight, do i need to have tax to take it to the mot station? recently tax dads bike online and there's a tick box confirming the vehicle has MOT? Quote Link to comment Share on other sites More sharing options...
ItsMatt Posted June 12, 2015 Report Share Posted June 12, 2015 getting the bike in for its mot tomorrow, im going to insure it tonight, do i need to have tax to take it to the mot station? recently tax dads bike online and there's a tick box confirming the vehicle has MOT? weird, I'm getting mine MOT'd for the first time (in my hands) tomorrow as well. to my knowledge you have to pass the MOT to be able to tax it Quote Link to comment Share on other sites More sharing options...
trials owns Posted June 12, 2015 Report Share Posted June 12, 2015 exacully what i thought, what do you ride? heres a picture of mine today Quote Link to comment Share on other sites More sharing options...
ItsMatt Posted June 12, 2015 Report Share Posted June 12, 2015 just a shitty old 50 I've had lying around for ages but done nothing with because cycling is faster and free not ever had it on the road properly, just a few plays around the garages. PEUGOT SQUAB 1997 (don't have a good picture of it because its just embarrassing, but its something) 1 Quote Link to comment Share on other sites More sharing options...
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