Qwik Posted September 27, 2023 Posted September 27, 2023 (edited) With having blown the motor on my Bandit Sidecar rig. I’m going to do a Big bore build. Does anybody have experience with either the APE or Holeshot kits? Anything to avoid? Any tips, tricks,? Any help would be appreciated guys Edited December 31, 2023 by Qwik Quote
DAZ Posted September 27, 2023 Posted September 27, 2023 I can understand why you want to go big bore on the replacement engine for you outfit,but imho I think for your application I would stick to a stock type rebuild,as all the big bore kits seem to hike the compression to around 12/13:1 which with the added load of a chair may be too much, if I were to make any mods it would likely be to find some gsx1100 f cams and lower the gearing to increase the mechanical advantage and keep the rpm in the sweet spot of max torque and hp . Just my opinion and as ever your ride your dime your choice 1 Quote
Upshotknothole Posted September 27, 2023 Posted September 27, 2023 Holeshot and APE have both been doing it for a long time. Holeshot probably has more experience with the bandits and doing mild street tunes on them. Give Holeshot a call first and see what they recommend, APE is good for machine work and any parts that Holeshot doesn't stock. I agree with DAZ, stay away from doing a crazy high compression build. Nothing wrong with going with forged pistons, but use a base gasket to keep the compression reasonable for using pump gas. Years ago a took a friend's bandit with a 1216 kit from Dale Walker for a test ride, big bore, lumpy cams, exhaust, and jet kit. Tons of mid range power, and a nice lumpy idle like an old muscle car. Quote
Qwik Posted September 29, 2023 Author Posted September 29, 2023 (edited) Well after about an hours worth of conversation with Dale Walker on the phone. I have a set/kit of pistons on the way. Cylinder is already been shipped to the machine shop to be bored. Cometic head gaskets on the way. Should be around 11 to 1 compression. The machine already has a Holeshot stage 2 set up on the jetting/pipe. This thing ran good before. It’s gonna run really good now Edited September 29, 2023 by Qwik Spelling errors. 5 Quote
clivegto Posted September 30, 2023 Posted September 30, 2023 I bought a 1277cc motor that came out of a grass track outfit 1 Quote
Qwik Posted September 30, 2023 Author Posted September 30, 2023 Questions for those who will know. Should I increase cooling with the 1216kit? And with an 81mm bore, will I lose the taper in the bore? Thus needing ring compressor pliers? Quote
Qwik Posted October 30, 2023 Author Posted October 30, 2023 On 9/27/2023 at 2:10 AM, DAZ said: I can understand why you want to go big bore on the replacement engine for you outfit,but imho I think for your application I would stick to a stock type rebuild,as all the big bore kits seem to hike the compression to around 12/13:1 which with the added load of a chair may be too much, if I were to make any mods it would likely be to find some gsx1100 f cams and lower the gearing to increase the mechanical advantage and keep the rpm in the sweet spot of max torque and hp . Just my opinion and as ever your ride your dime your choice Turns out it’s only up to 10.8 to one. 81 mm bore. Still curious if I need to do more cooling. Should I be replacing the head stud bolts with new? Any other ideas? Quote
Upshotknothole Posted October 30, 2023 Posted October 30, 2023 You could always swap out the stock oil cooler for one a bit larger. The GSXRs always came with larger coolers than the bandits. 1 Quote
Dezza Posted October 30, 2023 Posted October 30, 2023 2 hours ago, Upshotknothole said: You could always swap out the stock oil cooler for one a bit larger. The GSXRs always came with larger coolers than the bandits. It is mandatory on any OSS bike that a larger (preferably aftermarket) oil-cooler with fancy fittings is fitted, and for oil cooled bikes whenever possible, an additional head cooler too . 2 Quote
DAZ Posted October 30, 2023 Posted October 30, 2023 As above, most run after market coolers ,not that the stock cooler is ineffective, mostly for a safety margin and cos they look cool ,mocal and hel are good brand names but plenty of chinesium ones used too Quote
Joseph Posted October 30, 2023 Posted October 30, 2023 8 hours ago, Upshotknothole said: You could always swap out the stock oil cooler for one a bit larger. The GSXRs always came with larger coolers than the bandits. 50% more hp = more heat to dissipate i guess Quote
Qwik Posted December 31, 2023 Author Posted December 31, 2023 Well finally took the time to open up my Engine. Now I need to figure out why that cylinder went lean. Had to be over 1150° to melt that piston like that 1 Quote
Qwik Posted December 31, 2023 Author Posted December 31, 2023 I already have the JE Pistons kit and a set of freshly bored cylinders. Conrads look like they’re OK. But I want to go through everything just in case. in the meantime. I’m putting this in so that I can take my time to build this motor, right 1 Quote
Gixer1460 Posted December 31, 2023 Posted December 31, 2023 10 hours ago, Qwik said: Well finally took the time to open up my Engine. Now I need to figure out why that cylinder went lean. Had to be over 1150° to melt that piston like that That ain't lean! I'd say it was quite rich possibly excessively! Witness the 'wetter' crown / valves and the cleaner appearance. The damage is detonation - see the spotting / pitting around the edges of the chamber on the head. Head doesn't appear to be massively skimmed but difficult to tell - what did the plug look like (if it survived)? Possibly leaky float valve & excess fuel = detonation? Piston crown looks well thin with some cracking but whether that was pre or post failure would be a guess! Sidecars are a strange breed - high rpm + high load for long periods - they usually kill gearboxes and being fully enclosed cooling is usually a big issue as cooling ducts add drag - I am assuming this is a racing sidecar? 3 Quote
Qwik Posted December 31, 2023 Author Posted December 31, 2023 (edited) It’s a Street rig. Mostly used for riding long trips and sometimes for rippin twisties. When the failure occurred I was at about 55 or 60 mph on the highway. Headed home from a 2300mile road trip. 40 miles from home it did this. Not heavy revs and a fairly light load in the sidecar (clothes and camping gear) the whole outfit weighs less than 750lbs empty Edited December 31, 2023 by Qwik Quote
Qwik Posted December 31, 2023 Author Posted December 31, 2023 Yeah, funny, they tend to like the sidecar more than being on the back of the bike. Quote
Gixer1460 Posted December 31, 2023 Posted December 31, 2023 Maybe not the kind of engine I'd associate with a 'chair' ! Some of the diagnosis still stands though (maybe!) Quote
Qwik Posted April 13 Author Posted April 13 Motor is done. 81 mm bore, 1216 cc. 11.2 to 1 compression. Well the head was off we redid the valves. Made sure everything was good. Cleaned up real nice. Trying to figure out jetting. I will be doing a lot of trips to sea level and although I live at 7900 feet elevation. I think I would rather have it jetted for sea level. Trying to get this thing dialed in for long road trips. Nice thing with the tub as I can Carry a tent, a cot, sleeping bag, nice size cooler. And all the goodies 2 Quote
Qwik Posted May 9 Author Posted May 9 Well it’s all in. Tried to fire it up tonight. Take a lot to crank it and even with ether it didn’t even cough. So evidently no spark. Gotta figure that one out but I’m running out of time. Supposed to leave Friday for a week long trip and I was gonna try and break in the engine on the ride. I bought a 2011 KTM990 Adventure last Saturday. So I guess I’m gonna be on two wheels. Damnit Quote
clivegto Posted May 11 Posted May 11 On 5/9/2024 at 3:40 AM, Qwik said: Well it’s all in. Tried to fire it up tonight. Take a lot to crank it and even with ether it didn’t even cough. So evidently no spark. Gotta figure that one out but I’m running out of time. Supposed to leave Friday for a week long trip and I was gonna try and break in the engine on the ride. Is it done yet Quote
Qwik Posted May 12 Author Posted May 12 19 hours ago, clivegto said: Is it done yet Engine is in. No spark. Gonna take it down to my mechanic when I get home from my roadtrip. In San Simeon Ca right now headed north 1 Quote
Qwik Posted June 10 Author Posted June 10 Decided to try and figure this out. My mechanic is buried in work. Mess with it a bit tonight. Make sure everything was plugged in and tight. Still nothing Quote
DAZ Posted June 10 Posted June 10 Probably obvious but double check the earths ,if it was spinning over ok you would suspect the ignition side but not cranking and not firing up, first point I'd check is earths Quote
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