help withxj750 e2 29r

Hi all, was wondering are there and experts at the 29r bike. I bought the bike cheap as a non runner and the head had been pulled and stripped quite some time ago. The plan was to buy a new engine which I've located, but when I stripped the carbs all the jets/needle were wierd sizes. So I've discovered I've one of those '83 29r bikes that I know nothing about. Bike is stripped for blasting and powder coat but stuck not knowing will standard engine run ok with the carbs I have, and the ic igniter.
Also when ordering parts ie. fork seals, brake pads, bearings ect. will I order 900 parts from same year.
I would rebuild the engine but rust has crept in on the valve stems and cylinder walls and prob. other places, and seems a problem.

 

How bad is teh rust ? Much or any pitting ? My donor engine had been left out in teh rain I think and ended up seized. The head though was more or less OK (no pitting on the cam lobes..) I swapped teh barrels for ones that were also affect but not as bad. The worst affected cylinder is now giving 135 psi compared to 145 generally (after fitting new rings). what looked bad on the valves rubbed off easily.

 

Honestly have only visually checked them as I had a donor until this afternoon. Cams are in good order, all valves are labelled although fired in a box but the stems look fairly bad, will try and clean them tomorrow. All the shims and buckets are all over the place although all there so that would be fun to sort. Fairly concerned with ring of corrosion around the top of the cylinder walls.
Tempted to throw in the donor and see how she runs, shame to split the numbers on the bike though as there not too many 29r's

 

If the 'ring of corrosion' is right at the top (above where the top ring runs - or close enough) you could be in luck. Best bet would be to try and get it together with shims close to spec and try a compression test.

Ignitors can be swapped for similar models I think but wiring needs to be double checked - the 600 and 550 are quite different for example with the connectors swapped around.

 

Quick update, sorry been bogged down. Half the valve stems are gone too far with corrosion after cleaning so am going to send all bits for paint and get a donor engine and worry about the running when that comes. Lot of stuff to do before then.
Do you know are the jets and needles readily available for these carbs?

 

I don't know about availability of jets etc but hopefully here's some useful info

Years & Models: 1983 XJ750E-II models
Carb Manufacturer: Hitachi
Carb Series: HSC33
Carb Model ID: 29R00
Main FUEL Jet Size: #105 (cylinders #1 & #4)
Main FUEL Jet Size: #102 (cylinders #2 & #3)
Pilot FUEL Jet Size: #40
Main AIR Jet Size: #70
Pilot AIR Jet Size: #225
AIR COMPENSATOR Jet Size: not used.
Starter FUEL Jet Size: #43 (non-replaceable, in float bowl)
Main jet NEEDLE ID: #Y-17
Main needle JET Size: #3.2mm (the main needle JET is also known as the "power valve" or "emulsion tube").
Fuel Level in float bowls: 5mm +/- 1mm (.197" +/- .039")
Idle RPM's: 1,050 rpms

Although not part of your carbs, your valve clearances should be considered as part of your "intake system", so here are those specs, too. Note that valve clearances should be measured with the engine "cold", meaning 70-degrees Fahrenheit or less:

Valve Clearance Intake: 0.11 - 0.15mm ( = 0.004 - 0.006")
Valve Clearance Exhaust: 0.16 - 0.20mm (= 0.006 - 0.008")

And
MODEL NAME: XJ750E-II
STREET NAME: 1983 XJ750
MODEL ID CODE: 29R
FRAME ID: 29R
SERIAL NUMBER STARTS AT: 000101
NOTE: this model had a slightly larger (by 1cc) 749cc engine with larger valves, hotter cams, and Hitachi HSC33 series carbs, all fitted into the XJ900 frame. Anti-dive front suspension, XJ900 style fairing and bodywork. VERY rare.

The above info is from here
http://www.xjbikes.com/forums/index.php?threads/tech-topic-model-id-and-vins.14577/ see clickable logo top right of this page

 

You got a goofy bike my friend. Be glad you found a donor. Definitely keep the originals if you are gonna do a swap. Chacal has a bit of info on your bike, and there are several guys on here that have them. I suggest making friends with them.

 

Thanks Bushy. Been busy tinkering but all parts are back from refurb. so starting to rebuild. I'd promise pics but I'm so crap at remembering to take them, maybe one at the end.