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Blipp

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About Blipp

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  1. We bought a cr85 engine sight-unseen that had supposedly been pro built but our inspection revealed that it was assembled poorly. It had very nice parts in it like a new race prepped crank & etc. but the piston ring was installed wrong & chewed the cylinder. Also the seals & case 1/2 gasket were installed wrong so the engine was seriously sucking trans oil & we were not able to test ride it before we split the cases to reassemble it. Now that it's been rebuilt & were able to ride it the rider reports that it sticks in 2nd gear when the trans is accel or decel loaded & we don't know if it did that before the rebuild or not. The shift lever sticks hard & will not shift up or down until it's clutched &/or slowed down. Above or below that it shifts fine, makes no abnormal noises, & there's never been debris in the oil. We inspected the transmission carefully when we split the cases & saw nothing damaged but didn't think to check for incorrect assembly of the clusters. The shifter components under the right case cover & clutch look OK & it seems to shift fine on the bench. Before we split the cases again we wondered if anyone else has experienced this problem with a CR80-CR85 & what they found. We're hoping we missed something simple like a weak or incorrectly installed shifter detent spring... wishful thinking...
  2. Blipp

    Pilot Circuit on CRF450

    I'm not disputing you Burned but enough owners install new screws missing o-rings, improperly orient the washer/o-ring, or install screws with new o-rings while the old o-ring is still stuck in the bore that this guy might want to re-check his before rejetting the bike since he didn't mention any previous screw or jetting issues.
  3. Blipp

    How to destroke a XR100 or stroke a XR75?

    We got a XR75 crank & I guess to answer our own question here's what we found: While the size, style, & rough dimensions of the crank appear close there are serious differences that make them useless to us. It is basically identical to the CRF80 crank, but the stroke is shorter. The crank stud journals of the CRF80/XR75 are much smaller than the CRF100 so the CRF100 bearings will not just slide on to let you drop the thing in CRF100 cases & visa versa if you were to try to drop a CRF100 crank into a CRF80 or XR75. The crank bearings are smaller OD & ID. It might be possible to stick a XR75 crank in bored XR80 cases that will accept our trick top end but the expense would be more than destroking the CRF100 crank & we'd have the new problem of the weak CRF80 cases & the cylinder base flange that won't accept our big bore. There are no off the shelf bearings that would adapt the 2 that we have found yet, but we are looking. The XR75 cam chain drive gear has one less tooth & a CRF100 cam drive gear is too big for the XR75 crank stud. The XR75 connecting rod big end is much smaller than the CRF100 & the rod too short for enough dwell to let the big bore breath @ the RPM we need to see. The rod small end doesn't have enough material to be bored over to the CRF100 size safely. If we changed pistons the pin size would be too weak to support the HP these things make. So, we'd have to bore the crank for a CRF100 rod or have a custom piston made & risk blowing the thing & that would be exactly where we are now. Also, the drive gear end of the XR75 crank [like th CRF80] is smaller than the XR100 crank & we were already shearing the XR100 crank stub off, so it will not work.This near new XR75 crank is useless to us & is now for sale if anyone would like to make an offer before we run it on eBay.
  4. One pays a Japanese translation service to translate them like we had to.
  5. Blipp

    How to destroke a XR100 or stroke a XR75?

    Maybe we weren't clear? We need to know if the XR75 or other stock Honda under 43mm stroke Honda crank will fit in the XR100 case with a main bearing change or other minor mods. That's it. It looks like it will fit in diagrams & specs & there are guys out there that did the reverse of that so it's probably do-able, but we'd like some confirmation that it will before dropping $200+ on a new crank to see ourselves. We're shopping used cranks for checking purposes, but don't have one here yet to check & would have to rebuild it before use. In response Minifig: The XR80 cases, top end, clutch, & some gears/shafts are too weak for this application. We already have proven, bulletproof, winning combinations that never DNFd so we will stick with the combos we have. The main problem with the xr80 is the cases main bearing bores & cylinder skirt hole are both way too small & too poorly supported for this power & rpm level & some XR80 gears/shafts don't last more than a few laps without chunking or starting to seize on the shaft. That's why all that is bigger & better supported in the xr100 & we beef them up from there. You can definitly build a fun XR80, but it has no advantage in our application. A benefit to destroking our existing combos is we keep the entire package except for the timing chain & crank by simply shaving the cylinder or a longer rod. A side benefit is we can also go back to big bore if the rules change again with a crank, chain change, & a fresh cylinder. Since we keep 3-4 big bore spares on the shelf the crank swap is the most cost & time effective way to do it. Another benefit to reducing stroke & keeping our existing top end is what we lost by destroking we're nearly making up for with more top end, a better rod/stroke ratio, & a wider powerband. With more dyno time, & what is probably a lighter crank, we'll probably close the gap. The one that we destroked won it's class & nearly won the next class up despite being very de-tuned for a rich low RPM break-in mode, so the idea definitely needs no rethinking. It works for us. We race multiple classes & can use the XR100 cranks for seasonal rebuilds of the bigger class engines so swapping cranks is the smart thing to do. All THAT is why all we need to know is if the XR75 crank or similar stroke Honda crank [the longer the rod the better] will drop into the XR100 cases with a bearing change or other minor mod. Anybody know? THANKS!
  6. Well... We now have English instructions for this ignition. They don't help much. Kitaco themselves & Classic Honda [their USA distributor] both verbally say that you shouldn't kick start a bike with this ignition, push only, & Kitaco & Classic don't mention that fact in any sales info even though they both admitted being aware of the problem for many years. They did not say they were working on a solution. We spent a week going back & forth to the dyno to sort out all the new ignition & jetting issues the Kitaco caused us & I'm convinced that the Kitaco, out of the box, is real piece of crap. I'm also convinced that the USA distributor of them is screwing up a lot of XR100 engines to make a profit, but that is just my experience. The dyno indicated that the Kitaco does give more RPM, which makes sense since it has no rev limiter other than the engine grenading from what we could see, & an illusion of more power over other ignitions due to the odd ignition curve we suspect Kitaco borrowed from a weed whacker. ACS you can flip the pick-up over in both kits we tried. No keying or anything. MinifigPhil- We run several carbs on several bikes. The bike we tested it on was a known winner that runs a heavily modified/machined Mikuni Flatslide that outperforms any of the Keihins we've messed with. I see Minifig has his fully retarded on the plate & the pick-up & that far off I'm surprised his runs at all. I'm thinking his flywheel is mis-cut, he has a twisted crank stub, or something odd. That would be roughly 40+ degrees retarded normally. We turned up a trick little flywheel weight for the Kitaco & that helped the starting & low end but it sheared the kicker splines after roughly 10-15 starts when the timing was set for max dyno power. The breakage is caused by a combination of too light a flywheel & uneccesarily advanced low RPM timing. If you've got the inner rotor in your bike & hear a light knocking sound in the bottom end that is likely the too light flywheel failing to absorb the harmonics slapping the con rod & the timing chain around. It divots the con rod big pin caused a bad enough valvetrain chatter that it also chewed divots in hardface rockers. We're working on another ignition now. Not an inner rotor, but a much smaller outer rotor & so far it seems promising. Custom curve so we can start the things.
  7. Our race series changed cc limits outlawing 4 of the CRF100 based bikes our team built for the series. We destroked 1 to fit the cc limit & it won it's first race so we're now looking for a cheaper way to destroke the other 3. Does anyone know if the XR75 or any other less than 43mm stroke Honda crank will drop into the XR100 engine with just a main bearing change or minor mods? It looks like guys have been using the XR80-XR100 45mm stroke crank int eh XR75 so we're thinking the reverse of that might be do-able. Anybody know? We are aware of & can handle piston, connecting rod length, & timing chain issues.
  8. Guys, sorry for the long dealy, we ran out of time last season for messing with this Kitaco POS & went back to the modded stock ignition to complete the year & start this one. We pulled the Kitaco out & are giving it a last try. Not sure if it makes a differnce but our other bike runs the Kitaco coil, this one said to use the stock coil & change the cap for the Kitaco one. And by the way, we use O2 sensors & can say this is definitely not a jetting issue although IF we can get this piece of crap Kitaco to run right I'm sure we will be making some changes in the main jet air bleed circuit at least. We've wound this Kitaco around every which way & can't get it to run, the weird thing is the bike has never run better on the modded stock ignition so we know it can only be the Kitaco but we can't get any support on the thing. Anybody ever gotten these Kitaco instructions translated yet? ACS, I never got those pictures you promised, that might be a good restart. Still got them?
  9. RCannon, thank you for that detailed response. I'll PM this to you also. We took your advice & changed a few things. We've applied some of our thermal bonded ceramics & lubricants, have gone to a modified Phathead set-up so we can quickly try various combos, & have gone to the late flatslide, which so far is giving us some headaches on this combo, but seems to have potential. Haven't really settled on a pipe yet, what did you go with?
  10. Blipp

    CRF 480 heeellllp!

    I ride a ERC 480 with a JD Jetting kit & I'm very happy with it. I contacted Machster & ERC when I saw this thread because it sounded like ERC said to dump the JD Jetting. I found out ERC sorted out his problems while this thread ran, but Machster didn't post results & left us hanging. ERCs diagnosis was the same as yours but to clear things up they didn't tell Machster to dump the JD kit, they told him to recheck the carb assembly [plate] & go back to their suggested break-in jetting specs since it wasn't broken in yet. ERC gives you a break-in jetting specs, then when your engine is broken in they give you a choice of their help dialin in your jetting or suggest a name brand jetting kit. They suggested JD to me. With my bike the JD jetting didn't seem to make much difference over ERCs suggested jetting, but that doesn't mean there isn't a difference, maybe slightly crisper in the low/mid but I would have to do back to back tests to be sure. From what I understand Machsters Nephew ignored or misread the Honda Manual, JD instructions, & ERC install & break-in instructions. The cam timing was off & the carb slide plate installed upside down [probably], & the jetting off. Also, since MAchster rebuilt it because it was losing power & had become hard to start the valves were probably out of spec & ERC said it's common for people to cut corners & drop heads back on without adjusting the valves but not admit doing it, & that's what they think went on with Machsters bike re: the hard start.
  11. I seem to recall this being discussed here before but couldn't find it in a search: We picked up a '02 CR80 expert that we converted to race Supermoto. It has become clear that the '05-'06 CR85s have a power advantage. The class is restricted to 85cc. We've verified that there are at least 2 cheater big bores in the class, but winning isn't worth corrupting our children for life so we plan to play by the rules & keep it under 85cc. We're thinking about upgrading the '02 engine with '06 parts, since the chassis itself does very good. What are the differences between the '02-'06 CR80-CR85 other than bore size & exhaust pipe changes? Is it possible to bolt the top end from a '05-'06 onto this '02 & end up with a '05-'06 spec CR85? If so exactly what parts must be changed? Is the ignition different?
  12. If you're shopping eBay for one of these I strongly suggest sending me a PM so I can tell you who to avoid like the plague. They are clueless & if you press them to do their job they bail out on any kind of product support. Thank you for the input but in many CDIs you can fry the module using a lightbulb to time them, but that is a safe way to time a point ignition. I've been building/racing engines with CDI ignitions since the early '70s. It was installed exactly as the Kitaco diagragm shows, preliminarily set exactly like our other bike, & then the static timing was carefully re-checked with degree wheels, dial indicators, & a recording DMM to make sure we didn't screw up. We're confident that the problem is the ignition itself, not the installation, & to prove that to this seller beyond any doubt we need to check/verify some claims this seller has made & in the process we hope to help anyone else that may stumble accross a similar problem. So, has anyone out there got a clear picture of one in a bike that is known to work properly to prove what the proper pick-up orientation is? Has anyone out there had the Kitaco instructions translated, expecially the 2nd page? We particularly want to know if Kitaco ever suggested reversing the pick-up.
  13. We picked up another Kitaco XR100 inner rotor setup for our back-up/practice bike from a horrible eBay seller [PM me for their name because they are bad news & the only one selling these on eBay right now] & this one seems to be completely screwed up. It won't run well no matter what we've tried. Our other Kitaco equipped bike works OK but is in a trailer & gone for over a week for some riding & dialing in so we can't compare them. The seller claims that it is common for Kitaco to install the pickup backwards & they are telling us to just flip it over. They refuse to send us a diagragm or picture of a correctly assembled unit. This setup just preignitied the kicker into trash so we don't want to just flip it over & hope for the best. Has anyone else out there experienced the "backwards pick-up" this seller claims is very common? Does anyone out there have a photo or diagram of a pick-up that is properly installed & running in a XR100? Has anyone out there got English Kitaco instructions or had the Japanese ones fully translated? A factory mechanic acquantence translated part of ours but his English is as bad as our Japanese.
  14. Blipp

    2 blown motors

    Let's see; They bought another new CRF-450R from a company that just sold them a bike that grenaded... Odd... He MX raced a brand new CRF450. No mention of the rec. break-in day or changing or checking the fluids. Odd. Did the rider & owner fully read the manual? Did they make sure the Honda PDI tech tech properly filled the bikes fluids, & check the fluids before each ride like they are supposed to? The CRF250 had "10 rides" on it. How long was the total time of those rides? Most MXrs we deal with will bang out at least 3 hours total time per ride day & that means there's a good chance this bike had more than 30+ hours on it & was past due for service when it blew up. Was any of the required maintenance or a proper break-in performed? As a race tech I hear stories like this all the time & 99.9% of the time the owner didn't fully read their manual, didn't perform any required pre-race inspection or maintenance, & didn't check the fluids before riding, every time. Properly maintained CRF-250R & CRF-450R are very durable & effective race bikes as long as they are properly maintained. You can upgrade parts to wring more power & more life out of them but my suggestion for anyone is to read the owners manual of the bike you want to buy before you buy it. If you can't perform the recommended service intervals or can't afford them you should not buy the bike. FYI the CRF-450R is known to have a short lived pistons & the CRF-250R is known to have a piston that will develop cracks when left in beyond the suggested replacement interval. So if you ignore service intervals you are gambling your engine every time you fire it up. PM me & we'll negotiate buying the remains of the blown CRF-250R or CRF-450R engines for core parts to offset your costs a little.
  15. I just bought a JD jetting kit & think it would be a good idea to get a jetting baseline direct from JD since both bikes are on the wild side mechanically. They both currently run well & have been properly jetted but we'd like to see if we can get a bit more out of them with JD on board: 1st bike; '03 CRF450R 450cc seats reworked, ported, chamber smoothed, & ceramic coated head. Full Kibblewhite custom valvetrain, undercut valves, stock sizes. Hotcams Stage 2. 12.7:1 actual compression ratio, ceramic coated piston. Full Yosh Ti exhaust system. Twin air anti backfire filter [no screen]. Airbox opened up. '04 Ignition system with High rev box. This bike rides all the typical So Cal off-road venues, occasional Motard. 2nd bike; '03 CRF450R ERC 480cc kit, seats reworked, custom Ferrea Ti intake valves, 1mm oversize, custom steel Ferrea stock size exhausts, R/D springs, chamber smoothed, ported & ceramic coated head. Hotcams Stage 2 [Custom Webcam in the works] 12.5:1 compression. Full Akrapovic exhaust. Twin Air anti backfire no screen. Airbox opened up. '04 ignition w/ high rev box. Ditto the riding areas as above, except more Motard. Both run very well & have been jetted in but we just want to see if we can squeeze a bit more out of them with JD Jetting.
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