so, check this out.
on my hybrid, which now needs at min a set of pistons, i was working on it saturday. it has had a weird hesitation for years right off idle i havent been able to quite cure, but ran fantastic otherwise.
so, for at least 4 years, ive runt he same igntion curve, not changing it much from 2010 on the zeel. way back when i swapped over to the VM34s i also started using iridium plugs because i had some (br9eix). this seemed to allow me to run it a bit rich but keep it together without fouling plugs. (THIS IS RELEVANT.. KEEP READING)
So, I swapped over to the TM32's a year or more ago. Got it jetted and it ran even better. fyi setup was/is:
40 pilot, 1.75 out
5df? whatever it is needle. (notes at home on that)was on clip 2 (one lean)
P6 Jet tube
250 main.
mzb(vape)/zeeltronic box
always started 1st-2nd kick. running 40:1 and when fully warm between 175-195 water temp. (195 usually sitting at a light)
so, Saturday, I figured id address the off idle stumble or mis. so, as with tuning, i alwasy err richer and then move from there.
set carbs to:
260 main
middle clip
air screw at 1.5
and moved timing point at 3k to 22 degrees (up 2 degrees from where it was leaving all other points exactly the same, hence not affecting any other part of the curve past the next point, which is at 4200)
the other thing i changed was the plugs. went fromt he BR9EIX to a BR9ES.
warmed up bike, took for a ride and got water temp up to 170-ish. theres a long straight i test on about 2 miles from house, so when i got there i opened it up and it was running awesome. until it wasn't. somewhere in top of 5th gear at 110 mph it lost power. :eek: pulled clutch in and it stalled. :omg: water temp had spiked to 220. :bang:
coasted a few hundred feet and gently let clutch out and it spun and fired but was.. tappy. and on one cylinder.
limped it down the road a lightly and was ok but def dragging a cyl. pulled into the parking lot and immediately pulled the plugs. yup.
aluminum. :whatever:
mind you, this plug was on the side that wasn't firing after it lost power so its of course rich looking
heres the shots of all the plugs. from the br9eix (that it ran great on) to the b9es it blew up on.
neither were plug chops. and the iridium plugs last run was a warm-up on choke in the garage then off choke to warm bike up. so they look way rich.
so.. every carb circuit was richer. what happened from one day to the next? there were no air leaks. no timing changes over 3k. (was well over 9k when it went).
this is where it gets weird.
Friday, I went into the local MC shop with a very competent owner that sponsors quite a few MX racers. i was going to order a box of BR9EIX'S again, he didn't have any, also said that they had been having problems for a few years with them failing in races and went back to standard plugs with all failures eliminated, and that other teams had reported the same thing. TBH, didn't think much of it. till my motor went.
my theory is: i tuned it with a plug that was probably misfiring somewhat a few years ago.
I put in plugs that were working as they should and.... the bike was then jetted too lean. (even though i jetted it richer)
SO.. lesson learned. as I've said many times: most jetting issues are electrical.
rebuild time! hopefully just a set of pistons and a hone. it def didn't stick hard so maybe i got lucky.
So you were tuned with the iridiums, then switched to a good normal plug she destroyed herself?
What's the theory on what is happening with the iridiums?
exaclty.
what the racers had noticed was misfires and fouling at high rpms. they were tuned with regular plugs then switched to iridiums and thats where they saw the problems. reverse that and you 'create' a lean condition by having full spark events with non missing plugs. thats the theory i'm going with on mine.
Well, damn. Another wad of cash that turns into a good story (and a running bike).
true
TBH its been a LONG time since ive been in this motor because i needed to be. I dont mind TBH. It'll get other improvements as well on the rebuild. it always does. :toot:
I.am glad it didn't seize. I know it wilI be even stronger in the next iteration.
Let's try a theory here that the smaller electrode Iridium plugs don't retain as much heat so they run slightly cooler that stock fat wire plugs which get hotter at the tip and cause overheating.
If a fine wire burns more of the available fuel/air mixture, and fat wire standard plugs don't burn as effectively, why does that create an issue when it's not on the pipe. Unburned fuel should theoretically cool the combustion chamber and raise exhaust temperatures. At lower speeds that shouldn't hurt, it should help. Mabye at high revs that hotter exhaust is pushed back into the barrel by pipe resonance, causing a temperature rise in the exhaust port and combustion chamber at high revs.
Honest question. How does unburnt fuel crest higher exhaust temps?
I always appreciate a Teazer post!
Quote from: Czakky on May 24, 2021, 07:34:16 PM
Honest question. How does unburnt fuel crest higher exhaust temps?
I always appreciate a Teazer post!
It's because un burnt fuel in the combustion chamber is fuel burning in the exhaust. Just like when you retard timing, it lowers the head temp but increase egt, it burns slower.
Exactly.
it was def missing down low. for a few years. :twocents: years (10?) ago i went from regular plugs to iridium ones on the rz and saw no tune difference. It was what i did after i had one dialed in
I bought a set of 4 BR9HIX and blew my bike up on the first set. Was gonna try jetting on the second set and just running my old set after. Damn things aren't cheap ya know. But... maybe I should just order 5 sets of standard B8HS plugs if I can find them and let it eat...
I run them, haven't had a problem. However, with my RD before I sold it I was getting a miss at high RPMs and couldn't figure out why as I hadn't changed anything, for the hell of it I put new plugs in (iridium again) and it cleaned it up. They work great in my TZ.
yeah Chuck (my local guy) had 'matter of fact' told me some were an issue. Considering i was buying from him, he had no motivation to sell me a cheaper plug except for my benefit . I kind a blew it off at the time for the same reason. never had an issue. considering he goes racing every. single . weekend. (his kids and he also sponsors as well) hes 99% of the time right.
Its no different than a weak ignition causing low jetting. as far as 'plug heat' they were both '9' series.
So how old were the Iridium plugs that you put in?
Has the problem been fixed with the 2021 batch?
Not much online about it.
M
i probably bought them 3-4 ? years ago. beats me. I'll just go regular from here out.
I just bought a pair. :bang: :sad:
Quote from: m in sc on May 25, 2021, 02:24:05 PM
i probably bought them 3-4 ? years ago. beats me. I'll just go regular from here out.
I have like 8 i pitched. not worth the possible aggravation.
Interesting vid on fake sparkplugs causing misfires. They seem to be pretty difficult to tell apart from the real thing.
Most info I can find online about Iridium issues and misfires are fairly recent and could well be from fake plugs.
https://www.youtube.com/watch?v=7fyD1BXnhtY (https://www.youtube.com/watch?v=7fyD1BXnhtY)
i've heard about that but these were bought at a shop that gets them direct from rocky mtn . If i had ebayed them or amazoned, sure, but nope. these were legit. I never mail order plugs for that very reason.
So i finally pulled the topend off last night and no surprise... pistons are cooked.
there was no signs the rotor slipped, but this is def igntion related. melted the exhaust edge off the piston, which leads to late timing.
so, heres the damage. it happend quick too.
(http://www.2strokeworld.net/wp-content/uploads/LC-HYBRID/21-topend/lc-piston-melt_3.jpg)
(http://www.2strokeworld.net/wp-content/uploads/LC-HYBRID/21-topend/lc-piston-melt_2.jpg)
(http://www.2strokeworld.net/wp-content/uploads/LC-HYBRID/21-topend/lc-piston-melt_1.jpg)
and the head. looks fine. got lucky.
(http://www.2strokeworld.net/wp-content/uploads/LC-HYBRID/21-topend/lc-piston-melt_5.jpg)
the gasket is still on there and i have to clean up the piston slag.
the bores actually look good as well. so, im still leaning towards it having a misfire previosulsy, but not misfiring with the new plugs which exposed an obvious timing fault up high. as i said up top... NOTHING changed in the ign tune for th epast few years and i jetted UP prior to this run. so.. Not sure. either way, rebuild time.
Im not even mad. just glad it wasnt worse.
Glad it isn't any worse. I know you will figure out the cause.
still think it was the plugs (old iridiums) misfiring up top. I added spark and bam. im glad as well. but so it goes. :patriot:
Ouch. This is where a knock sensor would be super valuable. Unfortunately it's a hard ask.
it went so quick it was ridiculous.
I believe it. Things were hot in there.
Sorry about the overheating. Hope you get it cleaned up and back on the road in the near future.
appears to be NO damage or even aluminum on the bores so should be good
Burnt up and exited stage left in the exhaust. Glad the bores are ok!
Left side looks much hotter than right side. Looks like it's run lean but when it's detonating, the temperature rise tends to mask everything else.
The left appears to have eroded the front (exhaust side) and blown the particles down the pipe. I prefer fine wire plugs on high performance motors and have never experienced that sort of meltdown with iridum or standard plugs caused by the plugs even with plugs of too low heat range - say B7s or 8s.
Working back a step or two: If the old iridium plugs misfired, the exhaust temperature would probably be higher. If standard plugs improved the burn, the motor should have made more power and exhaust temps should have been lower because the burn would have been more complete.
What else changed? Was it perhaps a different fill of gas that wasn't as good as prior fills? Could the ignition timing have changed electronically for some reason? The answer should be No F'n way, but stuff does happen. Did it happen at high revs/load and were riding conditions any different. I'm sure you already asked yourself those questions and more, but that left piston missing the whole exhaust side ring land suggests that the problem was exhaust temperature prior to detonation. Was air density very high that day?
Left side looks much hotter than right side. Looks like it's run lean but when it's detonating, the temperature rise tends to mask everything else.
The left appears to have eroded the front (exhaust side) and blown the particles down the pipe. I prefer fine wire plugs on high performance motors and have never experienced that sort of meltdown with iridum or standard plugs caused by the plugs even with plugs of too low heat range - say B7s or 8s.
Working back a step or two: If the old iridium plugs misfired, the exhaust temperature would probably be higher.
disagree. it think it (unwittingly) misfired = 'rich' with the iridiums for a long time now. I then tuned carbs to run with those back when i put the flatslides on. However, I think i cured suspected (high rpm iridium) misfire with different plugs and i think it was what caused the issue. (at high rpm). def not a heat range thing.
If standard plugs improved the burn, the motor should have made more power and exhaust temps should have been lower because the burn would have been more complete.
i see what you're saying but .... with the timing retarded up over 9200, if it was misfiring slightly before and not now, would yes, complete the burn, but later due to the programmed retard and cause the front of the piston as BOTH did (look closely) keep in mind, i rode this home about 2 miles very carefully after this happened, so the mismatch of piston colors has zero to do with the blowup. (look at the plug pics)
What else changed?
larger main jet and one clip richer. thats it. should have had reverse effect if anything else.
Was it perhaps a different fill of gas that wasn't as good as prior fills?
same tank i rode it in last time so nope.
Could the ignition timing have changed electronically for some reason? nope. i checked it when i got back on the programmer and the mzb drum did not move, i have witness marks when i installed it
The answer should be No F'n way, but stuff does happen. Did it happen at high revs/load and were riding conditions any different.
typical day, was about 75 degrees. nice morning. was ridign normal till it warmed up, then yes, i railed on it. was shifting around 9.8- 10k.
I'm sure you already asked yourself those questions and more, but that left piston missing the whole exhaust side ring land suggests that the problem was exhaust temperature prior to detonation. Was air density very high that day?
again, look closely at pics of both pistons they actually have the same damage. ignore the color.
I know... its a loopy theory, but that was the ONLY thing that changed was the plugs and slightly richer jetting. and i will say, it took the needle position and main change well. flt better until it did what it did.
Think back to the old days when people would mistakenly jet leaner because of weak spark. I think this is basically what was happening here.
i wouldn't believe me either but i know exactly what changed. also, intakes, gaskets, etc look great, no signs of an airleak. Also, as stated my local guy said they quit running the iridiums in the race bikes over the past year or 2 because they were having spark issues. this was a few days before i installed them and bough the regular plugs from him. (actually bought them for the LT250 grom, they both use same plug)
Thoughtful response. That misfire thing still doesn't sound right to me. Doesn't mean I'm right, but let's walk through some of the possibilities.
If there's a misfire (electrical), some of the fuel and oxygen did not ignite. That absolutely happens with most ignition systems but we mere humans can only detect that missed cycle if there are lots of them - relatively speaking.
So, on that cycle without ignition, fuel and air pass into the exhaust where they may, or may not burn.
In terms of gas analysis, we see that as a high HC level but the Air:fuel ratio which measures unburnt oxygen, doesn't really make a huge difference to the Lambda reading, and the unburnt fuel makes little to no difference to the plug color because nothing burned so no heat effect to see. That's what we see with poor fuel atomization too. If fuel droplets are too large, not all the fuel gets vaporised and burned.
If the spark is "weak" and lights the fire, the flame propagation rate arguably is slower because the flame kernel is smaller and less intense, so we might expect that to show up again as more unburnt fuel and oxygen passing down the pipe.
If that is the case, we should expect lower average combustion chamber temperatures and therefore lower plug tip temperatures which we read as "rich". We know that when we read a plug, all we are really doing is to look at the temperature the plug reached, so rich jetting leads to lower combustion temps and sooty looking plugs. "Hotter" plugs like say a B6 run higher temps and self clean at lower running loads, with the same Air:fuel ratio we read hot plugs as if they are lean and harder (e.g. B10EGV) will tend to look rich with the same A:F.
That said, if the fine wires are not generating a sufficiently strong spark, they will run cooler that they should. We read that as rich and jet down. If replacement plugs generate a stronger spark which creates a more complete burn, then you get the result you describe.
The problem that causes me is that fine wire plugs are supposedly deigned to fire more consistently with inconsistent combustion conditions.
Your situation suggests that Iridium plugs are not only not better, but are actually worse in a high performance two stroke. I have not tested standard plugs back to back with say B*EGV or Iridium, but it's an interesting hypothesis. Needs a multi gas analysis on the dyno which are not typically available on dynojet but are on eddy current dynos we were lucky to have access to a few years ago.
Witness marks? Are those small scribe marks to line things up?
teazer, you're over thinking it soemwhat but yes.... this is what im driving at to quote your reply: "
That said, if the fine wires are not generating a sufficiently strong spark, they will run cooler that they should. We read that as rich and jet down. If replacement plugs generate a stronger spark which creates a more complete burn, then you get the result you describe."
the iridiums are presumed defective and misfiring. or actually missing spark. like a bad coil. (I am making this assumption/theory on the fact that my local mx guy who i bought the plugs from had fouling issues on his racers bikes using the same ones). this would require less fuel up top to run what seemed to be ok. Im not saying irridiums are bad by design. I'm saying i had a bad batch of them. there no other reason it would have failed like this. I'm not demonizing irridiums overall, hell, i ran them in my rz for 7 years and -NEVER- had a failuire.
I can 100% confirm this bike would do 120+ on the open road for good long runs prior with no overheating or detonation issues with water temps not going over 190. i added jetting and changed plugs and boom inside a half mile.
Mike, i always make witness marks on the ign rotor and bolt. if it moves, you'll know immediately by looking at it.
Mark,
Me overthinking things? Puleeze..... OK. Guilty as charged.
So with absolutely no hard data to work from, I decided to browse the source of all knowledge - the might interweb and there are so many opinions and half baked theories that it's kinda hard to draw any useful conclusions.
Some believe that Iridium plugs have a different thermodynamic profile and that the same heat (number) is misleading and that while Iridium and standard are the same temp at full load they are different at light load conditions. No data to support the theory but sounds interesting.
Others say that Iridiums improved power or smooth operating compared to Standard.
Odd incidences of Iridiums failing completely or misfiring. Not well documented but could be there's some bad plugs out there.
Some suggestions that Iridium is mandatory in high power motors and others saying that standards must be used. Two stroke sled manufacturers seem to like Iridiums and in some cases they want extended nose plugs and others say never use them.
The only good comment I found so far was that different applications need different plugs.
So if we discount all of the opinions, it comes down to why do some iridium plugs fail and are they actually any better in our low mileage applications, since none of us is expecting to get 100,000 miles between changes of plugs.
And in your case when the motor and jetting was set up running iridium plugs, did a simple change to standard plugs need the jetting to be revised?. Looks like it needed a large jetting increase. When you rebuild it and set it up for standard plugs and jet it on a dyno or butt dyno, it will be interesting to see how much more main jet it likes and to see the difference if you run that setup with iridium plugs after setting it up.
i wont run irridiums again. no point really as after i get one dialed in it never fouls plugs.
like said, i have experience with them but not in the past 5 years or so, except for THIS bike. and i ran them in the triples, and the rz with no tuning changes. I'm marking it up to a bad batch. as with anything mass produced, just a matter of time before some bad ones get out. I thnk i'll be in the 280-300 range. was at 260's which seemed small even on a p6 jet tube.
as an update:
pulling everything down and inspecting, i found no other possible issues (whew). I had to borrow a hone as they were on back-order for 6 weeks, so frank b came thru for me. after a light hone, was able to measure up and down the bore using a t gauge and then feeler gauge to piston skirt, all was in spec, hair over .0024" so luckily, no bore damage. checked all down the bore w the gauge and mic, on both cyls a BUNCH rotating the gauge and then the piston, seems good. due to lack of material transfer and the water temp never going over 220.. i figures as much but always safer to check. cleaned everything up, repainted, and am adding a temp switch int he head for a fan if its needed (haven't run one since 04 but I had it laying around so, why not). also moved the temp sensor for the gauge up into the upper hose so some plumbing updates. swapped back to studs on the exhaust, utilizing brass VW air-cooled exhaust nuts, and trying to get a better setup for the petcocks since its a dual feed tank w no crossover provision in the tank.
endless project. :devil: :toot:
(http://www.2strokeworld.net/wp-content/uploads/LC-HYBRID/21-topend/lc-reassemble-6-21_4.jpg)
(http://www.2strokeworld.net/wp-content/uploads/LC-HYBRID/21-topend/lc-reassemble-6-21_2-rotated-e1624288483728.jpg)
finally found an actual useful purpose for the pergola. (paint curing in sun)
(http://www.2strokeworld.net/wp-content/uploads/LC-HYBRID/21-topend/lc-reassemble-6-21_1-rotated-e1624288518204.jpg)
(http://www.2strokeworld.net/wp-content/uploads/LC-HYBRID/21-topend/lc-reassemble-6-21_5-rotated-e1624288554794.jpg)
(http://www.2strokeworld.net/wp-content/uploads/LC-HYBRID/21-topend/lc-reassemble-6-21_6.jpg)
compression was tested as assembled, not yet run. both cyls dead even. so.. the lesson here is.. always keep the clutch covered
Cool, I like that you get right at it and make it go again so quickly. Downtime is a bad thing. What pistons did you decide to go with? I have had those Iridium plugs in my bike for over a year and everything has been ok, but I notice it is harder to start now. Before I had the HPI ignition, the Dyna, stock coils, and regular plugs, would misfire at full load at high rpm (weak spark?). After thinking it was jetting, and many hours later, I put in fresh plugs and the misfire would stop but as soon as the plugs had just a little run time on them it would start misfiring again. The HPI made all the misfires stop and I didn't have to change the plugs any more. I think I will try the standard plugs and see if anything seems different.
thanks. same as before, pro-x. Im not a wiseco fan TBH. I have them in the lightweight but, meh.
and like said, i've run iridium's before with no issues. fwiw, the vape (or mzb) thats on the bike im fixing has been on since 2007.
Looks good!!
got 'oh shit' fan wired in on radiator as well. temp switch in head will kick on at 195. (this is primarily for getting stuck in traffic situations). its a small spal fan but it moves a shit tone of air.
carbs on, jetting up to 280 to start. still need to mount pipes and break in, will have to wait a day since i have family in town coming over for a dinner tonight.
In theorum... The properties of Iridium are very interesting from a scientific perspective. It is of the platinum group which means that it has catalytic properties when heated to high temperatures. These properties are similar but not identical to Pt. Functionally similar to what you see in vehicle catalytic convertors as an example. The reaction causes rapid oxidation of certain materials including aromatic hydrocarbons and the reaction is self-sustaining as long as fuel is present. The reaction is mostly initiated by heat of the catalyst. It is possible that sudden changes in iridium temperature would result in initiation of this catalytic reaction and fluorescence of the iridium component. That would react similarly to a glow plug and initiate detonation in the presence of fuel. At high RPM this could advance ignition or create a secondary ignition event from wasted spark under the right conditions such as high RPM.
Iridium is chosen for it's high resistance to arc transfer. In high energy ignitions that is desirable. But modern FI systems are better controlled for fuel delivery than carburetion. Fuel quench is available and utilized in charge temperature control and emissions are carefully managed. The amount of unburnt fuel is greater in a 2-stroke no doubt. If hot spots develop in iridium electrodes from high energy ignition spark, in the presence of hydrocarbons, the ignition event could be uncontrolled. In a 2-stroke application where there is a high energy spark and excess fuel I believe that a reaction would be possible.
I'm not saying that this is what happened with Mark's bike. It is just a possible explanation for what occurred with no other identified problems. What this would indicate is that iridium spark plugs are unsuitable for 2-stroke applications using high energy ignitions. Not that there are lot release problems in quality control in the plugs. I have no evidence to support this except laboratory experience using PT as a catalyst. It will self-sustain a reaction in the presence of hydrocarbons at the right temperature. It is only a possible explanation. Under ideal conditions... From my look into the properties if iridium the catalytic properties are less predictable than platinum. It would only take a momentary reaction at the wrong time to propagate detonation. That might present as a timing anomaly. It might not have the perfect conditions in any other engine for this to occur.
IR8D8R
i see what you're saying.
except it blew up when i took the iridium plugs out and the copper cores in. :huh:
Oh yeah. Well that makes me feel like I wasn't thinking well... :laugh:
I was so fuckused on the properties of iridium I outsmarted myself.
IR8D8R
you know, it was one of those rare instances where only one thing could have been the issue I was able to sort it out. especially since the bikes been put together so long and historically extremely reliable. I -never- would have even considered it unless for that happenstance conversation with Chuck S.
I was in there 2 days ago buying some fuel line and was talking to his main tech, and he was like 'yeah.. that's all it could have been.... so weird.'.
hopefully i can wrap it up tonight.
Aside from the pain in Mark's ass and the new hole in his wallet, this has been a great thread. Great reading, made me think and I may have even learned a thing or two.
NO PAIN REALLY im used to it being into these things this long. Pistons are a consumable service part.... sometimes. well, that service is accelerated a bit. However, keep in mind i could be completely wrong on my diagnosis. time will tell. Wont be the 1st time.
why its not running yet:
Yesterday I put in a heavier duty relay (actually went to an 85A continuous duty solenoid, marine style) for the galaxie as monday the twin fans were running intermittently on the way home and i'm not going to blow up my motor due to a 30 amp relay. so that rewire ate up last night, tonight is dinner with my brother but after that will prob dip into the garage and finish bolting the pipes on. :science:
I must have been asleep in class, but I just noticed that TZ water pump on the clutch cover. How did you mount and drive that?
On the R5 side cover I fitted one in place of the oil pump, but it sits on an adapter plate. That was a common conversion for karts back before my time. I had a pile of ex kart motors and bits a few years ago and that's where mine came from.
adapter plate as well. used the 'stock' tz drive and rd oil pump gear.
heres the paint curing last year in the sun when i resealed the clutch cover (had developed a slight seep)
(http://www.2strokeworld.net/wp-content/uploads/LC-HYBRID/2020/waterpump-mount/lc-pump-remount_04.jpg)
That's neat. I cut down the side cover a little further than yours and I think I used the RD oil pump gear IIRC.
I mistyped oil pump gear as well
so back together all good. however.. im wondering if indeed the rotor DID indeed slip. heres why: the washers under the m7 were a bit concave in. now, the witness marks i had put on seemed to still line up but when i verified it with my dial gauge and poiter ( i have a committed one out of aluminum i made). :whatever:
If it was out it wasnt much. i pulled the rotor, and machined a 3mm 316ss washer for the drum. bought some slightly longer m7 bolts and heated the rotor, used adash of sleeving loctite and ran it down.
jetting still at the richer settings, with a 280 main seems to like it ok. it does run -really- well but i didnt take it far had stuff to do today. But it may have been my dumbass the whole time. not sure. its seemed like it was maybe ony 1-2 degrees out if anything. :whistle:
You would think for the price of those ignition kits that they would include a nice hard thick washer. I noticed how the washer concaved on my HPI and installed 2 grade 8 washers.
Quote from: 1976RD400C on June 27, 2021, 06:53:39 AM
You would think for the price of those ignition kits that they would include a nice hard thick washer. I noticed how the washer concaved on my HPI and installed 2 grade 8 washers.
The thicker washer and bolt kit is only $12 at Economy
Quote from: m in sc on June 22, 2021, 11:22:02 AM
got 'oh shit' fan wired in on radiator as well. temp switch in head will kick on at 195. (this is primarily for getting stuck in traffic situations). its a small spal fan but it moves a shit tone of air.
carbs on, jetting up to 280 to start. still need to mount pipes and break in, will have to wait a day since i have family in town coming over for a dinner tonight.
How did the fan fit on your rad?
Its over 100 deg here at the moment (very un-Canadian) and my bike has been overheating so I fitted a fan from a GSXR that was in my parts bin.
Fits ok, but it is pretty wide and I had to move the rad forward about 2". Kinda loud as well but it does work.
IIRC, a few years back, it was discovered that copycat/fake NGK iridiums were being being sold. I presume, primarily online but there was a huge bad batch of vespa clutch bushings that were coming from reputable suppliers 5 or 6 years ago.
I find it incredible that this would be the problem here but it does follow the rule of "what did you F with last" method of troubleshooting:)
Glad to hear there was no physical damage to the rider, bikes can be fixed. In fact, OP will likely just make it faster :whistle:
the plugs were legit, i never order them online, ever. however, 99% sure it was the rotor slipping. wild speculation got the better of me.
I do know john sells the thicker washer (and i would recommend it) . However, i bought this unit way before john started selling them. Im pretty sure its the 1st one in the US after FLA Steve found them online. The one i have on the r5 has the upgraded washer. ;)